Can energy be created or destroyed during motion?

conservation lawArticle Free Pass
conservation law, also called law of conservation, in physics, several principles that state that certain physical properties (i.e., measurable quantities) do not change in the course of time within an isolated physical system. In classical physics, laws of this type govern energy, momentum, angular momentum, mass, and electric charge. In particle physics, other conservation laws apply to properties of subatomic particles that are invariant during interactions. An important function of conservation laws is that they make it possible to predict the macroscopic behaviour of a system without having to consider the microscopic details of the course of a physical process or chemical reaction.
Conservation of energy implies that energy can be neither created nor destroyed, although it can be changed from one form (mechanical, kinetic, chemical, etc.) into another. In an isolated system the sum of all forms of energy therefore remains constant. For example, a falling body has a constant amount of energy, but the form of the energy changes from potential to kinetic. According to the theory of relativity, energy and mass are equivalent. Thus, the rest mass of a body may be considered a form of potential energy, part of which can be converted into other forms of energy.
Conservation of linear momentum expresses the fact that a body or system of bodies in motion retains its total momentum, the product of mass and vector velocity, unless an external force is applied to it. In an isolated system (such as the universe), there are no external forces, so momentum is always conserved. Because momentum is conserved, its components in any direction will also be conserved. Application of the law of conservation of momentum is important in the solution of collision problems. The operation of rockets exemplifies the conservation of momentum: the increased forward momentum of the rocket is equal but opposite in sign to the momentum of the ejected exhaust gases.
Conservation of angular momentum of rotating bodies is analogous to the conservation of linear momentum. Angular momentum is a vector quantity whose conservation expresses the law that a body or system that is rotating continues to rotate at the same rate unless a twisting force, called a torque, is applied to it. The angular momentum of each bit of matter consists of the product of its mass, its distance from the axis of rotation, and the component of its velocity perpendicular to the line from the axis.

Energy exists in many forms, such as heat, light, chemical energy, and electrical energy. Energy is the ability to bring about change or to do work. Thermodynamics is the study of energy.
First Law of Thermodynamics: Energy can be changed from one form to another, but it cannot be created or destroyed. The total amount of energy and matter in the Universe remains constant, merely changing from one form to another. The First Law of Thermodynamics (Conservation) states that energy is always conserved, it cannot be created or destroyed. In essence, energy can be converted from one form into another. Click here for another page (developed by Dr. John Pratte, Clayton State Univ., GA) covering thermodynamics.
The Second Law of Thermodynamics states that "in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state." This is also commonly referred to as entropy. A watchspring-driven watch will run until the potential energy in the spring is converted, and not again until energy is reapplied to the spring to rewind it. A car that has run out of gas will not run again until you walk 10 miles to a gas station and refuel the car. Once the potential energy locked in carbohydrates is converted into kinetic energy (energy in use or motion), the organism will get no more until energy is input again. In the process of energy transfer, some energy will dissipate as heat. Entropy is a measure of disorder: cells are NOT disordered and so have low entropy. The flow of energy maintains order and life. Entropy wins when organisms cease to take in energy and die.
Potential energy, as the name implies, is energy that has not yet been used, thus the term potential. Kinetic energy is energy in use (or motion). A tank of gasoline has a certain potential energy that is converted into kinetic energy by the engine. When the potential is used up, you're outta gas! Batteries, when new or recharged, have a certain potential. When placed into a tape recorder and played at loud volume (the only settings for such things), the potential in the batteries is transformed into kinetic energy to drive the speakers. When the potential energy is all used up, the batteries are dead. In the case of rechargeable batteries, their potential is reelevated or restored.

BCA Semester 1: Physics - Forms of EnergyQ & A
Q(2013): (a) State Law of Conservation of Energy.
(b) Write the names of different forms of energy.
Law of Conservation of Energy: This law states that energy can neither be created nor be destroyed, but can change form. It means total energy of an isolated system cannot change. The total energy E of a system can change only by amounts of energy that are transferred to or from the system.
i.e. W = △E = △Emech + △Eth + △Eint
where △Emech = change in mechanical energy,
△Eth = change in thermal energy
△Eint = change in other type of internal energy of the system.
(b) Forms of Energy
|Type of Energy||Description|
|Kinetic||Due to motion of a body|
|Potential||Due to position or configuration of the body.|
|Mechanical||Sum of potential and kinetic energy of a body.|
|Electrical||Due to electrical field around a body.|
|Chemical||Due to atoms and molecules of a body|
|Magnetic||Due to magnetic field|
|Nuclear||Due to binding force between sub-atomic particles.|
|Gravitational||Due to gravitational Field|
|Radiant||Due to radiation including light|
|Thermal or Heat||heat energy due to difference in temperature|
|Intrinsic or Internal||Due to mass possessed by an object|
Q (2011): Does kinetic energy of a body depend upon direction of motion? Justify your answer.
Answer: No. Kinetic energy is a scalar quantity. It does not depend on the direction of motion. It depends on mass and magnitude of speed.

Gravitational potential energy U = mgh
g= acceleration due to gravity,
h= height above the surface, m = mass of the body.
According to this theorem, work done by all the forces acting on a body is equal to the change in kinetic energy of the body
Work done = Change in kinetic energy
Law of Conservation of Energy
According to the law of conservation, energy can only be transformed from one form to another. It can neither be created nor be destroyed. e.g., when an object is dropped from the height, its potential energy continuously converts into kinetic energy.
When an object is through upwards, its kinetc energy continuously converts into potential energy. The total energy before and after transformation always remains constant.
PE + KE = constant or mgh+1/2mv²=constant
Transformation of Energy
The conversion of energy from one form to other is known as the transformation of energy. The phenomenon of transformation of energy from useful to useless form is known as dissipation of energy.
- Green plants prepare their own food (chemical energy) using solar energy through the process of photosynthesis.
- When we throw a ball, the muscular energy which is stored in our body gets converted into kinetic energy of the ball.
- When an athlete runs, the body’s internal energy is converted into kinetic energy.
Einstein’s Mass-Energy Equivalence
According to Einstein, neither mass nor energy of the universe is conserved but they are interconvertible. The conversion is expressed by the equation E=mc²
c=3×108m/s is the speed of light

|The most important thing about energy is that it is conserved, which means that energy cannot be created or destroyed, it can only be converted into other kinds of energy. The total amount of energy remains constant. How many different kinds of energy are there? We know that mechanical energy consists of kinetic and potential energy, but energy can also appear in the form of heat, light, electric fields, magnetic fields, or even nuclear energy.
When we are talking about mechanical systems we are only concerned with kinetic and potential energy. Friction converts kinetic energy into heat, and so it represents a net loss of mechanical energy. Once energy is converted into heat it is for all practical purposes lost forever, because the heat will just drift off into the environment. This is what the brakes on a car do. In order to stop the car, the friction produced by the brake pads must generate a quantity of heat equal to the kinetic energy of the car, and as a result the brakes get very, very hot.
The law of conservation of energy can be stated in three (equivalent) ways:
- Energy cannot be created or destroyed, only changed into different kinds of energy.
- The total energy of an isolated system is constant. (An isolated system has no energy or mass entering or leaving it.)
- The Energy of an non-isolated system changes only by the amount added or removed. If the only energy involved is mechanical, this can be stated as W = DK + DPE, because the only way to change mechanical energy is to do work on the system. Doing work will either change the kinetic energy or the potential energy (or both) of the system.
Example: Rock falling off cliff of height h (ignoring air friction)
Initially, the rock has a PE of mgh (the work it would require to raise it that high from ground level). At first this is also the total energy of the system, because potential energy is the only kind of energy the system has at that time.
As it falls it loses PE and gains KE, but always the total energy remains the same. Since it started with a total energy of mgh, this will always be the total energy. On the way down, its energy will be a mixture of PE and KE, but will still add up to that original value of mgh:
This means that at a given height y we can calculate the velocity.

Conservation of Kinetic and Potential Energy
Energy comes in many different forms. It can’t be created or destroyed, but it can move between objects and change forms. The energy of motion of a moving object is called kinetic energy, and is given by the equation
KE = 0.5m(v^2)
Where m is the object’s mass, and v is the object’s velocity.
Another form of energy is called potential energy which is the energy an object has from being at a spot in a field where it would rather not be. When you lift an object up from the ground, the energy you put into lifting it becomes gravitational potential energy, given by PE = mgh, where m is mass, g is acceleration due to gravity (9.8 meters per second), and h is height. Pulling opposite poles of magnets apart or pushing identical poles close together also produces its own kind of potential energy.
When you stop holding up an object, it starts to fall, and that gravitational potential energy transforms into kinetic energy (when it actually hits the ground, the energy gets dispersed in a complicated mess of heat and mechanical deformation).
Whereas we could solve this problem using kinematic equations, conservation of energy makes these kind of problems much easier.
The total energy isn’t going to change from start to finish. It will just move entirely from potential to kinetic. At the start, it’s all potential, given by mgh.
(5)(9.8)(200) = 9800 J That’s joules by the way, the basic unit of energy.
This is all going to become kinetic energy, so:
9800 = 0.5m(v^2)
9800 = 0.5(5)(v^2)
3920 = (v^2)
sqrt(3920) = v = 62.6 m/s
This is an incredibly powerful trick. Using this method, we could even find how fast the rock is moving at any particular height just by finding the potential at that height, subtracting it from the starting total, and setting the leftover equal to kinetic energy.
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P1- Conervation and dissipation of energy
1 of 11
P1.1 - Changes in energy stores.
- Energy - stored in different energy stores
- transferred by heating, waves , electric current , a force when it moves an object.
- When an onject falls and gains speed its gravitational potentiall difference energy store decreases and its kinetic energy store increases.
- when a falling object hits the floor without bouncing, its kinetic energy store is transfered by heating to the thermal energy store of the object and surroundings. Sound waves move away from point of impact.
2 of 11
P1.2 - Conservation of energy.
- Energy - cant be created or destroyed!
- Conservation of energy applies to all energy changes.
- A Closed System = an isolated system where NO energy transfers take place in or out of the the system.
- Energy can be transferred between energy stores within a closed system.
3 of 11
P1.3 - Energy and Work...
- Work done is when a force makes an object move.
- Energy transferred = work done.
- Work done = Force x distance
4 of 11
P1.4 - Gravitational potential energy stores.
- Increases when object moves up.
- decreases when object moves down.
- Increases when lifted up as work is done.
- Gravitational field strength on Earth = 9.8N/kg
- The GFS on the moon is 1/6 less than earths.
5 of 11
Gravitational potential Energy Equation.
6 of 11
P1.5 - Kinetic and elastic energy stores.
- on a moving object kinetic energy store depends on its mass and speed.
- kinetic energy store ; E = 1/2 M X V^2
- elastic potential energy = energy stored in an elastic when work is done
- elastic potential energy in a stretched elastic; E = 1/2 k x e^2
- e = extention of spring ^^^^^^
7 of 11
P1.6 - Energy dissiaption.
- Useful energy is good! It goes to the place we want it too go to!
- Wasted energy is NOT GOOD! Its transferred by an undesired pathway.
- wasted enrgy is then transferred to surrondings, making it warmer.
- As energy dissipates (spreads) it gets less useful!!

What Are the Laws of Energy?
The laws of energy that govern interactions between matter and energy, such as the transfer of heat from one body to another in the physical universe, are most fundamentally defined by the three laws of thermodynamics and Albert Einstein's discovery of his special and general theories of relativity. Physics itself is built upon these laws, as well as the basic three laws of motion defined by Isaac Newton and first published in 1687, which explain the interaction of all matter. The field of quantum mechanics which began to emerge in the early 20th century also clarified special circumstances for the laws of energy at a sub-atomic scale, upon which much of modern civilization as of 2011 is founded.
One of the fundamental principles of the laws of energy made clear by the first law of thermodynamics is that energy is neither created nor destroyed. All forms of energy such as light or sound energy can be changed into other forms, and this was first revealed in the mid-1800s by the work of James Joule, a pioneering English physicist after which the basic unit of energy, the joule, was named. After ten years of thinking about the nature of the relationship between matter and energy, Albert Einstein published his famous formula in 1905 of E=MC2, that stated that both matter and energy were versions of the same thing and could be changed into one another as well. Since the equation states that energy (E) equals mass (M) times the speed of light squared (C2), it was actually stating that, if you had enough energy, you could convert it into mass, and, if you accelerated mass enough, you could convert it into energy.
The second law of thermodynamics defined the laws of energy by stating that, in any activity where energy was used, its potential diminished, or it became less and less available for further work. This reflected the principle of entropy and explained where energy went when heat or light escaped into the surroundings, which had puzzled humanity for centuries. Entropy is the idea that high levels of concentrated energy, such as that in fuel before it is burned, eventually spread out into space as waste heat and cannot be recovered. It was in harmony with the first law of thermodynamics because energy was not being destroyed, but access to it was lost.
The third law of thermodynamics was clarified in 1906 by research conducted by Walther Nernst, a German chemist.

The work, W, done by a constant force on an object is defined as the product of the component of the force along the direction of displacement and the magnitude of the displacement.
Calculation of Work:
When calculating work, only the force that is applied in the direction of motion is considered. W=Fdcosθ
If the force and displacement are in the same direction, that would be considered positive work.
Power is a measure of how quickly work is done.
Kinetic energy is energy of motion. All moving object possess kinetic energy.
Gravitational Potential Energy:
Gravitational Potential energy is the energy an object possessed due to its position.
The point that height is measured from. Any point can be used as a base level because the energy amount you calculate will be relative.
Conservation of Energy:
Energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes.

Mechanical energy is the energy which is applied to an object due to its motion or due to its position. Mechanical energy can be either kinetic energy (energy of motion) or potential energy (stored energy of position).
Conservation of Energy
As with momentum, energy is conserved in all interactions. The Conservation law of energy said that energy can’t be created and can’t be demolished, but only can be changed into other form of energy. In the 20th centuries, this definition has been expanded to include mass because they both are in a same form.
In this page, we will only deal with mechanical energy. While the potential energy decrease, the kinetic energy increases, means the total energy (mechanical energy) remains same before and after.
TEbefore = TE after
For there, an object is not conserving the entire energy, but there is some energy loss. This energy is not destroyed, but changed into other form or absorbed by another object.
When you pull the weight at a constant velocity, approximately how much pulling force do you have to supply? (Here we can say only approximately, because there is some friction force involved in the pulleys. If the pulleys have weight then the pulling force will have an extra weight of the lower set of pulleys where the actual weight is attached.)
If you assume frictionless and weightless pulleys , when you pull with constant velocity, you can answer the question by counting the number of ropes on the lower pulley that support the weight. For instance, in Figure 2 there are four ropes that are holding up the weight, so the pull force that you have to supply is only 1/4 as much as the weight. However, if the rope is wound around only one set of reels as in activity 3, then the pulling force is only 1/2 as much as the weight.
Now if you attach the rope on the lower reel to start with as in Figure 4, then the pulling force is only 1/3 as much as the weight because only three ropes are supporting the weight. If you have more than two sets of reels, for example, use six reels arranged into three reels on each set as in Figure 5, then the pulling force is only 1/6 as much as the weight.
If you attach the top pulley to the ceiling, the ceiling will be pulled by the weight and the force you supply plus the weight of all the pulleys.

Energy implies as the object’s capability to perform work. It is something that cannot be created or destroyed but can only be transformed. An object loses its energy, when it performs work, whereas it gains energy when the work is performed on it. Energy is broadly classified as kinetic energy and potential energy. While kinetic energy is the energy which an object contains because of a particular motion.
On the other hand, potential energy is the stored energy, because of its state of rest. As both the two forms of energy are measured in joules, people get easily confused between these two. So, take a read of the article which will help you to understand the differences between kinetic and potential energy.
Content: Kinetic Energy Vs Potential Energy
|Basis for Comparison||Kinetic Energy||Potential Energy|
|Meaning||Kinetic energy refers to an energy present in the object, due to its property of being in motion.||The energy, contained in an object by virtue of its position, is called potential energy.|
|Transferability||Can be transferred between objects.||Cannot be transferred between objects.|
|Measured from||Place itself||Bottom|
|Environment-relative||Relative to the environment of the object.||Non-relative to the environment of the object.|
|Equation||0.5 mv^2, where m = mass and v = speed||mgh, where m = mass, g = gravity and h = height|
Definition of Kinetic Energy
Simply put, the energy of motion is kinetic energy. The work required for accelerating the object of a certain mass, from the state of rest to motion. To speed up an object, we apply force, through which energy is transferred from one object to another, causing the object to move at a new and constant speed. The energy transferred is called kinetic energy, determined by speed and mass of the object, i.e. the greater the mass and speed, the more kinetic energy it contains.
The kinetic energy of an object, in motion, with a certain velocity, is same as the work performed on it. All the objects that are in motion or action, irrespective of horizontal or vertical motion, possess kinetic energy. It is the energy which an object acquires, owing to its state of motion. For example, Falling of coconut, flowing of a river, moving of car or bus, etc.

As we know that energy is the capacity of the physical system to perform different tasks, without it no work can be done. When the work is done, the energy gets transferred from one body to the other as the external force, or sources always apply in the process of the work done. At the same time, it should be kept mentioned that the energy can neither be created nor be destroyed. Around everything in the world possesses energy, but that doesn’t mean that energy always makes sure the work was done. The energy can even be stored within the body. By object’s status with even possessing the energy, we mainly have two types of energy. One of which is the kinetic energy and the other is the potential energy. As both of them have the SI unit joule, people often found it difficult to differentiate it between both the types of energy. Kinetic energy is the type of energy, which a body possesses by the property of being in the motion. Contrary to this, the potential energy is the type of energy, which a body possesses by virtue of its position is known as the potential energy.
What is Kinetic Energy?
The kinetic energy is the type of energy which a body possesses due to the virtue of being in the motion. In other words, we can say that the kinetic energy keeps the object in the motion. The motion of the object is evaluated with relation to the environment of the object. If the object changes its position with respect to the environment, then it is said to be in the motion. When the object is in the position of rest, and we pull it, but due to a heavy mass, it doesn’t move. To make it move we apply more of the force on it. At last, the object gets in the motion. In all this process, the energy is transferred from the one body to the other to produce acceleration in the object carrying certain mass is known as the kinetic energy. The kinetic energy is directly dependent on the speed and mass; the greater the speed and the mass, the more the kinetic energy of the body. When the moving object finally stops, in then the kinetic energy gets converted into the potential energy which puts an object on the rest. A misconception here prevails that the energy comes to an end, so the movement of the object stops, but that is not the case as the energy can’t be created nor be destroyed.

The Big Idea
Energy is a measure of the amount of, or potential for, dynamical activity in something. The total amount of energy in the universe is constant. This symmetry is called a conservation law. Physicists have identified five conservation laws that govern our universe.
A group of things (we’ll use the word system) has a certain amount of energy. Energy can be added to a system: when chemical bonds in a burning log break, they release heat. A system can also lose energy: when a spacecraft “burns up” its energy of motion during re-entry, it releases energy and the surrounding atmosphere absorbs it in the form of heat. A closed system is one for which the energy is constant, or conserved. In this chapter, we will often consider closed systems; although the total amount of energy stays the same, it can transform from one kind to another. We will consider transfers of energy between systems –- known as work-– in more detail in Chapter 8.

Examples may be seen above, and many others can be imagined (for example, the kinetic energy of a stream of particles entering a system, or energy from a laser beamadds to system energy, without either being either work-done or heat-added, in the classic senses).
ΔE = W + Q + E (3)
Where E in this general equation represents other additional advected energy terms not covered by work done on a system, or heat added to it.
Energy is also transferred from potential energy (Ep) to kinetic energy (Ek) and then back to potential energy constantly.This is referred to as conservation of energy. In this closed system, energy cannot be created or destroyed; therefore, the initial energy and the final energy will be equal to each other. This can be demonstrated by the following:
Epi + Eki = EpF + EkF
The equation can then be simplified further since Ep = mgh (mass times acceleration due to gravity times the height) and (half mass timesvelocity squared). Then the total amount of energy can be found by adding Ep + Ek = Etotal.
Energy and thermodynamics
Internal energy is the sum of all microscopic forms of energy of a system. It is related to the molecular structure and the degree of molecular activity and may be viewed as the sum of kinetic and potential energies of the molecules; it comprises the following types of energy:
Type |Composition of internal energy (U) |
Sensible energy | The portion of the internal energy of a system associated with kinetic energies (molecular translation, rotation, and vibration; electron translation and spin; and nuclear spin) of the molecules. |
Latent energy | The internal energy associated with the phase of a system. |
Chemical energy | The...

In the physical sciences, mechanical energy is the sum of potential energy and kinetic energy. It is the energy associated with the motion and position of an object. The law of conservation of mechanical energy states that in an isolated system that is only subject to conservative forces the mechanical energy is constant. If an object is moved in the opposite direction of a conservative net force, the potential energy will increase and if the speed (not the velocity) of the object is changed, the kinetic energy of the object is changed as well. In all real systems, however, non-conservative forces, like frictional forces, will be present, but often they are of negligible values and the mechanical energy's being constant can therefore be a useful approximation. In elastic collisions, the mechanical energy is conserved but in inelastic collisions, some mechanical energy is converted into heat. The equivalence between lost mechanical energy and an increase in temperature was discovered by James Prescott Joule.
Many modern devices, such as the electric motor or the steam engine, are used today to convert mechanical energy into other forms of energy, e.g. electrical energy, or to convert other forms of energy, like heat, into mechanical energy.
Energy is a scalar quantity and the mechanical energy of a system is the sum of the potential energy which is measured by the position of the parts of the system, and the kinetic energy which is also called the energy of motion:
The potential energy, U, depends on the position of an object subjected to a conservative force. It is defined as the object's ability to do work and is increased as the object is moved in the opposite direction of the direction of the force.[nb 1] If F represents the conservative force and x the position, the potential energy of the force between the two positions x1 and x2 is defined as the negative integral of F from x1 to x2:
The kinetic energy, K, depends on the speed of an object and is the ability of a moving object to do work on other objects when it collides with them.[nb 2] It is defined as one half the product of the object's mass with the square of its speed, and the total kinetic energy of a system of objects is the sum of the kinetic energies of the respective objects:
The law of conservation of mechanical energy states that if a body or system is subjected only to conservative forces, the total mechanical energy of that body or system remains constant.

Some Examples of kinetic energy Of daily life can be the movement of a roller coaster, a ball or a car. For example, a demolition ball stores energy when it is held high without activity. Do you know that working of a bow and arrow employs the first law of thermodynamics, which says that ‘energy can neither be created nor be destroyed; it can only be transferred from one form to another’? Hence, snow starts moving down the mountain swiftly. The planets revolving around the sun, the atoms spinning around the nucleus, a soccer ball that is moving or even a fish swimming are some of the examples of systems that possess mechanical energy. Like a rock about to fall off a precipice, a fruit in a tree has the ability to detach at any time due to the attraction exerted by gravitational forces on Earth. This is it for now. They include watching television, washing clothes, heating and lighting the home, taking a shower, working from home on your laptop or computer, running appliances and cooking. Dryer 3. The natural world has used the sun’s energy since the beginning of time, and while there has been lots of discussion about this, the truth is that the sun is both a problem and a solution. Some Examples of potential energy That we can find in the day to day are a swing, a demolition ball, a trampoline, a balloon or a pistol with spring, among others. When the bowstring is released, the arrow moves forward very quickly. Wind energy can be converted by a wind turbine that does just that. A dart gun works on the principle of elastic potential energy. Calculator 15. Read More: 6 Companies that Have Great Environmental Initiatives. But energy can not exit on it's own. The more an archer pulls back, the more potential energy will be gained by the limbs of the bow due to stretching. As we now know that the energy present in an object which is held at rest is called the potential energy. Water falls from the sky, converting potential energy to kinetic energy. Where does this energy in our body to do all the work comes from? When two spherical bodies move at the same speed but have different mass, the larger mass body will... 2 - Roller coaster. Thus, the potential energy of the stone is converted into a kinetic energy. Heating system 9.

If a car of of mass M stops due to retardation of frictional force , after
traversing a minimum distance then work energy theorem gives
Conservation of energy :
If a system is acted on by conservative forces, the total mechanical
theory of the system is conserved i.e. Mechanical energy E = KE + PE constant
i.e E = T + U = constant
(under conservative forces).
Other forms of energy :
In addition to mechanical energy, there are other forms of energy e.g. thermal energy, light energy, sound energy, electrical energy, chemical energy, nuclear energy etc.
If the system is under the action of non-conservative forces, the conservation law for mechanical energy does not hold and a more general law stated as “The total energy of the universe remains constant” holds. This simply means that energy may be transformed from one form to another. For example in loudspeakers, electric bells the electrical energy is converted into sound energy while in electromagnet electrical energy is converted into magnetic energy and for a ball falling on earth, the mechanical energy is converted into heat energy etc.
Einstein’s Mass Energy Equivalence :
According to Einstein neither mass nor energy of the universe is conserved separately: but mass and energy are interconvertible according to relation
This relation is called Einstein’s mass energy equivalence. Accordingly,
“Total (mass + energy) of universe is conserved”. This is the most general law of conservation of energy.
According to mass energy equivalence the body of mass at rest has rest energy therefore the kinetic energy of the body
Where m is the mass of the body moving with speed v given by
Coefficient of Restitution :
When the two bodies collide directly, then the ratio of relative velocity after collision to the relative velocity before collision is a fixed quantity. The quantity
is called the coefficient of restitution. Here u1, U2 are initial velocities and are final velocities of two bodies. The value of e lies between O and l. For a perfectly elastic collision e = 1 and for a perfectly inelastic collision e = 0.
If a body falls freely from a height H on a floor and bounces back to a height h. Then initial velocity u is given by,
and the final velocity v is given by
Elastic and Inelastic Collisions :
Elastic collisions :
A collision is said to be elastic if the total kinetic energy before and collision remains the same.

Conservation of mechanical energy equation
What is the formula for conservation of mechanical energy?
The conservation of mechanical energy can be written as “KE + PE = const”. Though energy cannot be created nor destroyed in an isolated system, it can be internally converted to any other form of energy.
What is the conservation of mechanical energy?
In physical sciences, mechanical energy is the sum of potential energy and kinetic energy. It is the macroscopic energy associated with a system. The principle of conservation of mechanical energy states that if an isolated system is subject only to conservative forces, then the mechanical energy is constant.
Is the mechanical energy conserved between A and B explain?
Mechanical energy is conserved so long as we ignore air resistance, friction, etc. Energy is “lost” to friction in the sense that it is not converted between potential and kinetic energy but rather into heat energy, which we cannot put back into the object.
What are the 3 types of mechanical energy?
Mechanical energy is the energy that is possessed by an object due to its motion or due to its position. Mechanical energy can be either kinetic energy (energy of motion) or potential energy (stored energy of position).
What are 5 mechanical energy examples?
Kinetic Mechanical EnergyRadiant Energy: Energy produced by light waves.Electrical Energy: Energy produced by electricity.Sound Energy: Energy produced by sound waves.Thermal Energy: Energy produced by heat.
What is work formula?
Work is done when a force that is applied to an object moves that object. The work is calculated by multiplying the force by the amount of movement of an object (W = F * d).
What is mechanical energy in simple words?
The energy of an object due to its motion or position; the sum of an object’s kinetic energy and potential energy.
Is a windmill an example of mechanical energy?
Wind Mill Windmills are the structures that convert wind energy into electrical energy and this energy is then supplied to our homes. Windmills run on the principle of mechanical energy and work. Moving air (wind) possesses some amount of energy in the form of kinetic energy (due to motion).
Is a roller coaster an example of mechanical energy?
Kinetic energy is energy that an object has because of its motion. All moving objects possess kinetic energy, which is determined by the mass and speed of the object. In a roller coaster, the forms of kinetic are mechanical, sound and thermal.

The difference between a conservative and a non-conservative force is that when a conservative force moves an object from one point to another, the work done by the conservative force is independent of the path. On the contrary, when a non-conservative force acts upon an object, the work done by the non-conservative force is dependent of the path.
Conservation of mechanical energy
According to the law of conservation of mechanical energy, the mechanical energy of an isolated system remains constant in time, as long as the system is free of friction and other non-conservative forces. In any real situation, frictional forces and other non-conservative forces are present, but in many cases their effects on the system are so small that the law of conservation of mechanical energy can be used as a fair approximation. Though energy cannot be created or destroyed in an isolated system, it can be converted to another form of energy.
Thus, in a mechanical system like a swinging pendulum subjected to the conservative gravitational force where frictional forces like air drag and friction at the pivot are negligible, energy passes back and forth between kinetic and potential energy but never leaves the system. The pendulum reaches greatest kinetic energy and least potential energy when in the vertical position, because it will have the greatest speed and be nearest the Earth at this point. On the other hand, it will have its least kinetic energy and greatest potential energy at the extreme positions of its swing, because it has zero speed and is farthest from Earth at these points. However, when taking the frictional forces into account, the system loses mechanical energy with each swing because of the work done by the pendulum to oppose these non-conservative forces.
That the loss of mechanical energy in a system always resulted in an increase of the system's temperature has been known for a long time, but it was the amateur physicist James Prescott Joule who first experimentally demonstrated how a certain amount of work done against friction resulted in a definite quantity of heat which should be conceived as the random motions of the particles that comprise matter. This equivalence between mechanical energy and heat is especially important when considering colliding objects. In an elastic collision, mechanical energy is conserved — the sum of the mechanical energies of the colliding objects is the same before and after the collision. After an inelastic collision, however, the mechanical energy of the system will have changed. Usually, the mechanical energy before the collision is greater than the mechanical energy after the collision.

If you've ever witnessed a video of a space shuttle lifting off, the chemical reaction that occurs also releases tremendous amounts of heat and light. Another useful form of the first law of thermodynamics relates heat and work for the change in energy of the internal system:
While this formulation is more commonly used in physics, it is still important to know for chemistry.
energy can be transferred and destroyed, but may not be transformed., energy cannot be created or destroyed, but can be transferred or transformed., energy can be created, destroyed, transferred, and transformed., or energy in the universe is constant; therefore, destroying it would lead to its re-creation.
Source: Boundless. “The First Law of Thermodynamics.” Boundless Biology. Boundless, 21 Jul. 2015. Retrieved 28 Nov. 2015 from https://www.boundless.com/biology/textbooks/boundless-biology-textbook/metabolism-6/potential-kinetic-free-and-activation-energy-69/the-first-law-of-thermodynamics-347-11484/

At a height y its PE is mgy and its KE is mv2, but their total is still the original amount of energy mgh, so
mgh = mgy + mv2,
from which it follows that
Notice that we can find v at any point without knowing any details of the path!
At the very bottom, just before it hits, all the PE will be converted to KE,
mgh = mv2
When the rock hits the bottom, all of the KE will be lost. Some will be spent breaking the rock and ground into pieces, some will go off as sound waves, and some willgo into doing work on the ground by compressing it. All this moving matter will experience friction, which converts KE into heat. Wherever all the energy goes, it must still add up to the original amount mgh.
Example: Block sliding down ramp with or without friction
Suppose a block is released form rest at the top of the ramp and allowed to slide down. How fast will it be going when it reaches the bottom? You could solve this problem by using the equations for constant acceleration, but it is much simpler to solve using conservation of energy.
The initial energy, when the block is at rest at the top of the ramp, is purely gravitational potential energy. If we measure the height h from the bottom of the ramp, the initial energy is
Ei = mgh
When the block reaches the bottom of the ramp. All of this potential energy will have been converted into kinetic energy, which is given by
Ef = mv2
But because energy is conserved, and we are assuming that we are not losing any mechanical energy through friction, the initial and final energies must be equal. Thus
Ei = Ef
mgh = mv2
which can be solved to give the final velocity as
If we allow for friction while the block is sliding down the ramp, we have to take into account the amount of mechanical energy that will be lost due to friction. The work done against friction will be
Wf = Fkd,
where Fk is the force of kinetic friction,
Fk = Nmk,
And d is the distance traveled along the ramp.

“Energy cannot be created or destroyed, it can only be changed from one form to another.”
― Albert Einstein
This year his theory of gravitational waves were detected therefore proving Einstein’s theory.
He figured it out in 1916, and 100 years later – we verified he was right.
Why should we care about gravitation waves? What about energy? There are many other discoveries just around the corner. We have just touched the surface on the transformation of energy.
We know the world has two geographic poles, the polar N and S. That is earth’s magnetic field at play. Imagine a massive magnet bar inside of the Earth, and you will get an idea what Earth’s magnetic field is shaped like.
Now earth does NOT have a giant bar magnet inside it – but it does have a field made by rotating swirling motion of molten iron around Earth’s outer core.
So we have the North Pole and the South Pole. The world also has two magnetic poles: the North Magnetic Pole and the South Magnetic Pole. The magnetic poles are near, but not exactly in the same places as the geographic poles. So two different things, a geographic pole and a magnetic pole.
The needle in a compass points towards a magnetic pole. The compass needle points pretty much due North unless your in the Southern Hemisphere – it points South.
However, if you are near either pole, the compass really becomes useless. It just points to the magnetic pole, NOT the TRUE geographic pole.
Our magnetic field is also tilted a little bit. So on an angle of about 11°, it is no guess that the magnetic poles and the geographic poles are not in the same place. I will note the magnetic poles actually move around. The spinning motions of the our planet’s magnetic field, the swirling motions, are changing all the time.
The magnetic field is actually changing, therefore the magnetic poles move. In the 1800s the poles moved an estimated 5.6 miles per year. For some reason, after 1970, they started moving faster. Recently they are moving around 25 miles per year.
The Northern and Southern Lights happen near the magnetic poles because of the charged particles (protons and electrons).
While our magnetic fields and energy are fluctuating – our Universe continues to expand. Our world is constantly moving, vibrating, and traveling in circular patterns.
A proven fact is all forms of matter contains an underlying energy of vibration.

Kinetic Energy is the energy of an object (mass) in motion. All moving objects have kinetic energy. A simple example of kinetic energy differences would be considering the idea of being hit by a football or by a fast moving car. The car being heavier and moving faster has much more kinetic energy than the soccer ball.
Calculating Kinetic Energy
The kinetic energy of an object can be calculated using the formula below:

The energy that is lost forms heat in the environment.
It is understood that without energy it is not possible to do work.
Energy is understood as the capacity of a body or mass to carry out work after being subjected to force. It is understood that without energy it is not possible to do work.
The energy of a body is related to its speed or its position. That is why thepotential energy, which is what a body possesses when it is at a certain height with respect to a reference system, from theKinetic energy, which is the energy possessed by a body that is in motion.
The unit by which energy is measured (the same as work) is the Joule (or Joule). One Joule represents the amount of work done by a constant force of 1 Newton, over a distance of 1 meter in the same direction as the force.
It is also possible to measure energy by calories (one Joule is the same as 0.24 calories).

Kinetic energy is motion of waves, electrons, atoms, molecules, substances and objects. The types of kinetic energy are:
- Radiant energy is electromagnetic energy that travels in transverse waves (light, x-rays, gamma and radio waves).
- Thermal energy, or heat, is the energy that comes from the movement of atoms and molecules in a substance (geothermal energy of the earth).
- Motion energy is energy stored in the movement of objects. The faster they move, the more energy is stored (wind).
- Sound is the movement of energy through substances in compression/rarefaction waves. Sound is produced when a force causes an object or substance to vibrate.
- Electrical energy is delivered by tiny charged particles called electrons, typically moving through a wire (lightning).

is the capacity of a physical system to perform work. Energy exists in
many forms like heat, mechanical, electrical, and others. According to
the law of conservation of energy, the total energy of a system remains
constant. Energy may be transformed into another form, but it is
constant within a system.
For example, we all know
two pool balls eventually come to rest after colliding. They stop
moving only because the applied energy
(from moving the cue stick) is eventually converted to heat (from
friction with air and the table) and sound (which is not very much of
the energy loss). The ball movement along the table's felt
surface and through the air transfers energy outside the two
moving balls to the air and environment around the table and into the
table itself. The temperature of the table and air rises ever so
slightly, because the applied energy moves outside the system we "see"!
Since the heat energy is spread all around in a very large area, we
don't notice the temperature rise. We just notice the balls quickly
example is our car's brakes. The energy stored in the moving weight of
the car is converted to heat by friction of brake pads rubbing against
metal rotors attached to the rotating wheels. This converts stored
energy (the engine put into the weight of the vehicle) into heat, and
the heat (containing all of that energy) radiates out into the air.
Most of what we actually do in a car is move heat around.
Newton's first law
mass continues in its state of rest, or continues uniform motion in a
straight line, unless it is compelled to change that state by forces
impressed upon it.
guys like Newton sure had a lot of time on their hands to think about
simple things, but they got it right. A rocket coasting through outer
space is a good example. It will go on forever in a straight line
unless it hits something, or unless gravity or some other force
pulls it in a new direction.The earth wants to move in a
straight line, except gravitational attraction to the sun bends its
path constantly. A bullet reacts the same way, except friction with air
and gravity changes the direction and speed gradually over distance.

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Thermodynamics is the study of heat energy and other types of energy, such as work, and the various ways energy is transferred within chemical systems. "Thermo-" refers to heat, while "dynamics" refers to motion.
The First Law of Thermodynamics
The first law of thermodynamics deals with the total amount of energy in the universe. The law states that this total amount of energy is constant. In other words, there has always been, and always will be, exactly the same amount of energy in the universe.
Energy exists in many different forms. According to the first law of thermodynamics, energy can be transferred from place to place or changed between different forms, but it cannot be created or destroyed. The transfers and transformations of energy take place around us all the time. For instance, light bulbs transform electrical energy into light energy, and gas stoves transform chemical energy from natural gas into heat energy. Plants perform one of the most biologically useful transformations of energy on Earth: they convert the energy of sunlight into the chemical energy stored within organicmolecules.
Thermodynamics often divides the universe into two categories: the system and its surroundings. In chemistry, the system almost always refers to a given chemical reaction and the container in which it takes place. The first law of thermodynamics tells us that energy can neither be created nor destroyed, so we know that the energy that is absorbed in an endothermic chemical reaction must have been lost from the surroundings. Conversely, in an exothermic reaction, the heat that is released in the reaction is given off and absorbed by the surroundings. Stated mathematically, we have:
We know that chemical systems can either absorb heat from their surroundings, if the reaction is endothermic, or release heat to their surroundings, if the reaction is exothermic. However, chemical reactions are often used to do work instead of just exchanging heat. For instance, when rocket fuel burns and causes a space shuttle to lift off from the ground, the chemical reaction, by propelling the rocket, is doing work by applying a force over a distance.

Mechanical energy can be termed as the energy of movement; as it is found in objects that are moving or have the potential to move. In physical science, it is the sum of potential energy and kinetic energy.
The formula for mechanical energy is;
Mechanical energy = kinetic energy + Potential energy
Law of Conservation of Mechanical Energy
It says that the mechanical energy of an object in a closed system remains constant if it is not under the influence of any dissipative force (for example friction, air resistance), except for the gravitational force.
Let us try to understand the concept of mechanical energy more plainly by taking a few examples from everyday life.
1. Wrecking Ball
A wrecking ball is a large round structure that is used for the demolition of buildings. When the ball is held at a height, it contains some amount of potential energy (stored energy) and as soon as it falls, it gains some amount of kinetic energy too. When the wrecking ball hits the building to be demolished, it applies the force (in the form of mechanical energy), which causes the work to be done, as in this case, the demolition of buildings.
Whenever we use a hammer to, let’s say, hit a nail and drive it into the wall, we are simply applying some force on the nail with the help of the hammer which is causing some work to be done. At rest, a hammer does not contain any kinetic energy but only some amount of potential energy. When we swing a hammer up to some distance from the nail before hitting it, kinetic energy comes into play, and the combination of kinetic energy and potential energy in the hammer, called mechanical energy, will cause the driving of the nail into the wall. Or, we can say that the force applied by the hammer to do work on the nail is mechanical energy, which is the sum of potential and kinetic energy.
3. Dart Gun
A dart gun is another example of mechanical energy observed in everyday life. A dart gun works on the principle of elastic potential energy. The spring used in the dart guns consists of stored elastic potential energy. When a dart gun is loaded, it causes the spring to compress. At that moment, the dart gun consists of elastic potential energy. Due to this energy, the spring is able to apply force on the dart and does work, i.e., displacement of the dart.
4.

The conservation of energy is thus intimately connected with the fact that the laws of physics are the same today as they were yesterday and as they will be tomorrow.
Scientists have been looking for over a century for any changes in the laws of physics with translations and rotations in space and with movement through time, and have never found any evidence for such changes. Thus momentum, angular momentum, and energy are strictly conserved in our universe. For the counter rotation device to create energy from nothing, all of physics would have to be thrown in the trashcan. The upset would be almost as severe as discovering that 1+1 = 3. Furthermore, a universe in which physics was time-dependent and energy was not conserved would be a dangerous place. Free electricity devices would become the weapons of the future—bombs and missiles that released energy from nothing. Moreover, as the free electricity devices produced energy from nothing, the mass/energy of the earth would increase and thus its gravitational field would also increase. Eventually, the gravity would become strong enough to cause gravitational collapse and the earth would become a black hole. Fortunately, this is all just science fiction because free electricity isn't real.
Generators and motors are very closely related and many motors that contain permanent magnets can also act as generators. If you move a permanent magnet past a coil of wire that is part of an electric circuit, you will cause current to flow through that coil and circuit. That's because a changing magnetic field, such as that near a moving magnet, is always accompanied in nature by an electric field. While magnetic fields push on magnetic poles, electric fields push on electric charges. With a coil of wire near the moving magnet, the moving magnet's electric field pushes charges through the coil and eventually through the entire circuit.
A convenient arrangement for generating electricity endlessly is to mount a permanent magnet on a spindle and to place a coil of wire nearby. Then as the magnet spins, it will turn past the coil of wire and propel currents through that coil. With a little more engineering, you'll have a system that looks remarkably like the guts of a typical permanent magnet based motor.

Where there are no opposing forces, a moving body needs no force to keep it moving with a steady velocity as we know from Newton's first law of motion.If, however, a resultant force does act on a moving body in the direction of its motion, then it will accelerate (Newton's second law of motion) and the work done by the force will become converted into increased kinetic energy in the body. So how we calculate it?.
1Start with the formula for work: work done = mf × s , where m = mass of the object, f = constant acceleration, and s = linear distance over which the force is applied.Ad
2Relate velocity, acceleration, and distance by Applying the equation v² = u² + 2 fs where v is the terminal velocity of the object and u is the initial velocity . Assuming the object starts from rest, u = 0.
3Solve for acceleration to get a = v² / 2x
4Substitute into the equation for work done = m × v² / 2s × s = kinetic energy or kinetic energy ( k.e.) = 1/2 m v²
5Since the work required to accelerate an object exactly equals the kinetic energy imparted to it, this expression, 1/2 m v ², gives the energy in joules or ergs according to the system of units used.Ad
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Simple explanation here. Live by these words: ENERGY IS CONSERVED. Gravitational Potential Energy (GPE) is stored energy. It is mgh. That is, mass times gravity times height. GPE is proportional to how high the object is. (GPE~h). The higher the object is, the more gravitational potential energy it contains. In most cases when we deal with GPE, we will, by convention, set the lowest point to be zero GPE (to make it easier for all of us). You can set any point to be 0 GPE but the lowest point is always the best place (unless specified in a question). -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Kinetic Energy (KE) is energy in motion, motional energy. It is 1/2m(v^2). That is, one-half of the mass times velocity squared. KE is squarely proportional to how fast an object is moving. (KE~v^2). The faster the object is moving, the more kinetic energy it contains. In most cases when we deal with KE, KE is 0 when the particle is not moving. For example, you throw an object in the air. At the highest point the object reaches, we say it is not moving at the instant and thus has no kinetic energy. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Now, we live by the words: ENERGY IS CONSERVED. By definition, the total energy of the system never changes. The potential energy and kinetic energy may change, but the total energy (KE+GPE) will not change. Now, when I dealt with energy, we were given a scenario that had an inital and final point. The forumla for the conservation of energy is: dKE = -dGPE (The change in kinetic energy is the negative change in potential energy) KE(f) - KE(i) = -[GPE(f) - GPE(i)] Distribute the negative sign KE(f) - KE(i) = GPE(i) - GPE(f) Separating final (f) and initial (i) KE(f) + GPE(f) = GPE(i) + KE(i) Flip it around... KE(i) + GPE(i) = KE(f) + GPE(f) And there we have it folks, the conservation of energy in simple terms.

In inelastic collisions, some of the mechanical energy of the colliding objects is transformed into kinetic energy of the constituent particles. This increase in kinetic energy of the constituent particles is perceived as an increase in temperature. The collision can be described by saying some of the mechanical energy of the colliding objects has been converted into an equal amount of heat. Thus, the total energy of the system remains unchanged though the mechanical energy of the system has reduced.
A satellite of mass at a distance away from the centre of Earth in space possesses both kinetic energy, , (by virtue of its motion) and gravitational potential energy, , (by virtue of its position within the Earth’s of mass gravitational field). Hence, total energy of a satellite is given by
If the satellite is in circular orbit, the energy conservation equation can be further simplified into
since in circular motion, Newton's 2nd Law of motion can be taken to be
Today, many technological devices convert mechanical energy into other forms of energy or vice versa. These devices can be placed in these categories:
- An electric motor converts electrical energy into mechanical energy.
- A generator converts mechanical energy into electrical energy.
- A hydroelectric powerplant converts the mechanical energy of water in a storage dam into electrical energy.
- An internal combustion engine is a heat engine that obtains mechanical energy from chemical energy by burning fuel. From this mechanical energy, the internal combustion engine often generates electricity.
- A steam engine converts the heat energy of steam into mechanical energy.
- A turbine converts the kinetic energy of a stream of gas or liquid into mechanical energy.
Distinction from other types
The classification of energy into different types often follows the boundaries of the fields of study in the natural sciences.
- Chemical energy is the kind of potential energy "stored" in chemical bonds and is studied in chemistry.
- Nuclear energy is energy stored in interactions between the particles in the atomic nucleus and is studied in nuclear physics.
- Electromagnetic energy is in the form of electric charges, magnetic fields, and photons. It is studied in electromagnetism.
- Various forms of energy in quantum mechanics; e.g., the energy levels of electrons in an atom.

Energy in a
Imagine throwing a ball against a wall
as hard as you can. What will happen when it hits the
Bounces Off Wall
Everyone knows that it will
Anything in motion has
kinetic energy---energy of motion. The kinetic
energy of the moving ball is converted to potential
energy as the ball is squashed into the wall. This
potential energy becomes kinetic energy again as
the ball springs back into shape and propels itself
away from the wall.
The change in the direction of the
ball is caused by the elastic nature of the ball itself.
Much like a spring, the ball "squashed" itself against the
wall then rebounds as it becomes round again.
Now imagine that the wall is moving
and has its own kinetic energy. At the moment of collision,
the wall transfers some of that energy to the
Remember the energy that the ball has when you throw it
against a wall? It has the same energy when it hits a bat.
But a swinging bat adds energy too. The combined energies
make hitting a home run easier when a baseball is
Now think about hitting a
baseball from a tee. All of the energy in this
system starts with the batter and is transferred to
the bat. Some of the energy in the bat is then
transferred to the ball causing it to fly off the
Hitting a baseball that is
pitched involves more total energy. The ball has
energy and the bat has energy.
Why are most home runs hit off of
© 2003-2005 Event-Based Science Project

If you watch long enough or there is appreciable friction, you will discern that energyy is also converted into heat.
Neglecting this production of heat, that is neglecting friction, we can write the total energy and conservation of energy as
Where h is measured above the lowest point. Note that the maximum KE occurs at h=0 and the maximum PE occurs where v=0, that is
Figure 2: The pendulum Bob at three positions. The KE and PE are indicated at each position.
Let's explore this example a bit further. To do so, we consider the free body diagram for the pendulum Bob including the tension in the pendulum wire and the gravitational force on Bob. This leads to:
At the lowest point of the swing, when the velocity has its maximum magnitude, the acceleration is centripetal, and directed straight up with magnitude
Substituting and noticing that ,
We can solve for the tension
Thus T the tension in the pendulum wire depends on the velocity, and is maximum when the KE is greatest, that is at the lowest point of the pendulums swing.
An interesting demonstration of this, and thus a way to confirm our application of conservation of energy to the pendulum Bob, is the set-up with a 1 kg Bob and a second, 2 kg mass (Pat) connected to the pendulum wire by way of a pulley as shown.
Pat will inform us when the tension in the string is greater than (the product of Pat's mass and the local gravitational field). This happens when
With the help of a little trigonometry, you can see that
And when .
When we tried this in lecture, we found that was not quite enough, because it is not true that "no energy is lost due to friction," even for a half-swing of the pendulum. When we made the angle slightly greater than , Pat was lifted a bit.
Return to Physics 125

(For more on the difficult issue of God's continuous recreation or preservation of the material world, see, e.g., Gorham 2004, Hattab 2007, and Schmaltz 2008).
It is obvious that when God first created the world, He not only moved its parts in various ways, but also simultaneously caused some of the parts to push others and to transfer their motion to these others. So in now maintaining the world by the same action and with the same laws with which He created it, He conserves motion; not always contained in the same parts of matter, but transferred from some parts to others depending on the ways in which they come in contact. (Pr II 62)
In the Principles, Descartes conservation law only recognizes a body's degree of motion, which correlates to the scalar quantity “speed”, rather than the vectorial notion “velocity” (which is speed in a given direction). This distinction, between speed and velocity, surfaces in Descartes' seven rules of impact, which spell out in precise detail the outcomes of bodily collisions (although these rules only describe the collisions between two bodies traveling along the same straight line). Descartes' utilization of the concept of speed is manifest throughout the rules. For example:
Fourth, if the body C were entirely at rest,…and if C were slightly larger than B; the latter could never have the force to move C, no matter how great the speed at which B might approach C. Rather, B would be driven back by C in the opposite direction: because…a body which is at rest puts up more resistance to high speed than to low speed; and this increases in proportion to the differences in the speeds. Consequently, there would always be more force in C to resist than in B to drive, …. (Pr II 49F)
Astonishingly, Descartes claims that a smaller body, regardless of its speed, can never move a larger stationary body. While obviously contradicting common experience, the fourth collision rule does nicely demonstrate the scalar nature of speed, as well as the primary importance of quantity of motion, in Cartesian dynamics. In this rule, Descartes faces the problem of preserving the total quantity of motion in situations distinguished by the larger body's complete rest, and thus zero value of quantity of motion.

Kinetic energy, also known as the energy of motion, is all around us in different forms. Without it, there would be no light, heat, sound, or movement. Only when the other major type of energy, potential energy, converts to kinetic energy are we able to see, hear, and move about. Kinetic energy even works at the molecular level. Vibrating molecules produce heat, and subatomic particles called electrons can flow together to create electricity. From the basic movement of atoms producing heat to a car screeching to a stop, kinetic energy affects our everyday lives.

Energy is conserved. The initial 1000 J of PE is transformed into 900 J of KE and 100 J of thermal and sound energy, heating herself, the air, and the slide.
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However, we often define a certain position as our reference point, i.e. h=0 with PE=0 at h=0. Adopting this convention,
For example, the floor is at h=0.
The work done in lifting a book can be stored as PE and then recovered. This is true no matter how the book was lifted, that is if it was accelerated and decelerated rapidly or slowly. In principle, we could lift and horizontally translate the book so that it is stored at a height h, but with a horizontal displacement. Since the book must first gain and then lose some horizontal velocity, first positive and then negative work is done on the book by who or what moves it. In many practical cases, the positive work is not actually "recovered," that is it is not stored in the same way that gravitational PE is stored. This is why it is often emphasized that "the book is moved horizontally very slowly," so that the extra work done is so small as to be negligible.
In cases for which the work done by an applied force can be completely stored as PE, we say that work is done against a conservative force. In the case of the book, the conservative force is gravity. Electrical forces are conservative, but frictional forces are not.
We will consider a large number of examples, including that of lifting the book, that demonstrate the Conservation Law of Mass/Energy. This law is best stated that any system has a total energy E that remains constant. The total energy is the sum of KE, stored energy (PE), heat, sound, etc. In fact heat and sound and many other forms of energy are manifestations of motion, that is of the molecules of an object and of air. The contribution to E will be discussed more in Lecture 16. Conservation of energy can be expressed as follows:
A long massive pendulum is a good example of conservation of energy because the amount of heat energy generated each cycle can be quite small compared to the maximum KE and PE. Focault used a pendulum, with a special pivot, that always swings in the same plane so that one can observe the earth turning underneath the pendulum swing during many hours, even days. As you observe the pendulum swing, you can watch energy converted from PE to KE to PE etc. as shown.

For the equations of the conservation of momentum, the units are not important, as long as the same ones are used before and after the collision (i.e. as long as we compare quantities measured in the same units).
m1 = 1500 kg v1 = 40 km/s
Let v3 be the final velocity of the wreckage. The conservation of momentum gives
m2 = 4500 kg v2 = -20 km/s
P = m1v1 + m2v2 = (m1 + m2)v3
1500*40 + 4500*(-20) = 60,000 - 90,000 = -30,000 = 6000*v
The wreckage moves at 5 km/s in the "negative" direction in which the truck was moving.
v = - 5 km/s
--Is kinetic energy conserved?
Not likely, since each of the masses (if we consider them separately after the collision) now moves more slowly than before.
--How much kinetic energy was lost?
If the result is to be expressed in joules, we better convert km/hr
1 km/hr = (1000 meter/3600 sec) = 0.27777 m/s
Initial velocities: v1 = 11.111 m/s v2 = 5.5555 m/s
Final velocity v3 = 1.3889 m/s
Kinetic energy =1/2 m v2
KE of the car (1/2) 1500 (11.111)2 = 92, 593
KE of the truck (1/2) 4500 (5.5555)2 = 69,444 joule
Total kinetic energy entering the collision 162,037 joule
Final KE (1/2) 6000 (1.3889)2 = 5,787 joule
Loss 156,250 joule
--Where did the lost energy go?
It probably went into heat.
--(Optional) "Humongous Airlines" publicized the smooth ride of its new "steadijet" airliner by installing a billiards table in its first class cabin. While the plane is flying at a steady velocity v0, do collisions of two billiard balls in it conserve momentum?
--Which velocities do we have to use in such a calculation--velocities relative to the airplane or to the ground?

In looking at a purported Free Energy (or perpetual-motion) machine we should thus look at the total interplay over a cycle between KE, PE and the three kinds of work (Stored KE, stored PE, displacement). Count the joules in and out and decide how to assign them in those 5 buckets. Do this assiduously and you can decide for yourself whether any Free Energy invention will actually work. The majority show a zero-sum overall when they are idealised to zero losses, so in real lossy life will just slow down and stop.
So, what does work? We know that solar panels work pretty well. We also know that if we have any cyclic motion or wave then we can rectify it and get some work done. One thing to remember is that the total energy doesn’t change – if we take some in one place it has to turn up in another. All we need to look for is a flow of energy that exists and to divert it so that it does what we want done before we let it go again. Displacement-type work does not take energy to perform, though there is an element of borrowing and returning from the energy bank. Energy is put in to start the motion, then the motion continues until we stop it and get the energy out again. That sword-to-ploughshare change is displacement-type work, in that no excess energy remains after the work has been done. The vast majority of what is normally regarded as work is displacement, where at the end of a cycle there is no work (KEwork or PEwork) actually done. Displacement work does not store any energy, and we should therefore be able to do it without using energy – all the energy we do put in ends up dissipated. At least we should be able to do it with a draw on the energy bank followed by a return of that energy.
I think it’s possible to harvest infrared to get a reasonable amount of electrical power. The Robert Murray-Smith experiments showed that in a small way, and it may be possible to get the harvest up by quite a few orders of magnitude. For this, we’re stopping an IR photon (which is moving energy) and converting it to electrical energy (moving electron in this case) and then either using it in some movement (so it’s re-emitted) or storing it in a battery as chemical potential energy for a later release.

You would then coast downward at a constant speed and would feel your normal weight. If you closed your eyes at this point, you would feel as though you were suspended on a strong upward stream of air. Unfortunately, this situation wouldn't last forever—you would eventually reach the ground. At that point, the ground would exert a tremendous upward force on you in order to stop you from penetrating into its surface. This upward force would cause you to decelerate very rapidly and it would also do you in.
When two objects collide with one another, they usually bounce. What distinguishes an elastic collision from an inelastic collision is the extent to which that bounce retains the objects' total kinetic energy—the sum of their energies of motion. In an elastic collision, all of the kinetic energy that the two objects had before the collision is returned to them after the bounce, although it may be distributed differently between them. In an inelastic collision, at least some of their overall kinetic energy is transformed into another form during the bounce and the two objects have less total kinetic energy after the bounce than they had before it.
Just where the missing energy goes during an inelastic collision depends on the objects. When large objects collide, most of this missing energy usually becomes heat and sound. In fact, the only objects that ever experience perfectly elastic collisions are atoms and molecules—the air molecules in front of you collide countless times each second and often do so in perfectly elastic collisions. When the collisions aren't elastic, the missing energy often becomes rotational energy or occasionally vibrational energy in the molecules. Actually, some of the collisions between air molecules are superelastic, meaning that the air molecules leave the collision with more total kinetic energy than they had before it. This extra energy came from stored energy in the molecules—typically from their rotational or vibrational energies. Such superelastic collisions can also occur in large objects, such as when a pin collides with a toy balloon.
Returning to inelastic collisions, one of the best examples is a head-on automobile accident. In that case, the collision is often highly inelastic—most of the two cars' total kinetic energy is transformed into another form and they barely bounce at all. Much of this missing kinetic energy goes into deforming and heating the metal in the front of the car. That's why well-designed cars have so called "crumple zones" that are meant to absorb energy during a collision.

We can understand this in terms of momentum flow:
Momentum-flow is represented by a double arrow, with two half-arrowheads. The colored part of the arrow shows what is flowing, while the black part of the arrow shows in which direction it is flowing.
It is characteristic of an equilibrium situation that we have a closed circuit of momentum flow. The momentum flows around and around, without any net accumulation anywhere.
This idea – closed-circuit flow with no accumulation – is similar to the first law of motion, only stronger: no net force means no change in momentum.
(For simplicity we have not considered the weight of the table itself; you can easily add that to the picture you want.)
In my experience, most people don’t have a problem with the idea of conservation when there is flow without accumulation. They have a pretty good intuition about continuity of flow in a loop. If anybody isn’t happy with this, put some water in a big round bowl and stir up a steady rotational flow. The water is conserved. The water is flowing, but for steady flow there is no accumulation anywhere.
Figure 11 shows my favorite demonstration of momentum flow. Balls #2 through #5 are initially at rest. Ball #1 swings in from the left. Momentum leaves ball #1 and flows through balls #2, #3, and #4 without accumulating. It accumulates in ball #5, which goes flying.
Figure 12 shows a video of such a thing in action: (Video courtesy of GiantNewtonsCradle.com.)
Trying to analyze this in terms of forces would be tricky. A reasonable amount of momentum is transfered in near-zero time, which leads to a near-infinite force.
Tangential remark: The usual Newton’s cradle apparatus has a special property that is often overlooked: At rest, the balls are not touching; there is a paper-thin air gap. Therefore when ball #1 arrives, there is not a single collision, but rather a rapid sequence of collisions.
There is a good physics reason for this:
|During an elastic collision between one ball and one other, conservation of momentum and conservation of energy give us two equations in two unknowns, so we can predict what happens.

This motion produced friction between the sandpaper and the wood, causing the molecules to move faster. As a result, both the sandpaper and the wood became hotter. Thus, the mechanical energy of the moving sandpaper changed into heat energy.
You were also the source of motion when you plucked the tight rubber bands, causing them to vibrate. Sound is produced when a force causes something to vibrate and produce sound waves. Sound energy is carried in waves.
Another way in which mechanical energy can produce sound waves is by tapping on a table. Tapping on the table causes the table to vibrate in the same way plucking on the rubber bands caused them to vibrate. Sound waves actually travel faster through the table than through the air. You can put your ear next to the table and hear the tapping sounds clearly. You can also raise your head and hear the sounds as the sound waves pass through the table and then through the air.
When electrical energy passes through a light bulb, it is changed into light energy and heat energy. Even though the heat energy is unwanted, it is still part of the electric bill. Engineers try to design light bulbs that increase the amount of light and decrease the amount of heat produced. Some progress has been made, but light bulbs continue to produce unwanted heat.
Start with the energy being given off from a TV or a radio in your home. Try to figure out where this energy comes from. See how far back you can trace the energy changes. This gets a little complicated, so get ad good reference book to help you.
What is the difference between an electric motor and an electric generator? They basically contain the same parts and are built the same way. However, an electric motor changes electric energy into mechanical energy, and an electric generator changes mechanical energy into electric energy.
In 1905, Albert Einstein proposed a theory that altered the law of conservation of energy. He said that matter can be changed into energy, and energy can be changed into matter, but the total amount of matter and energy in the universe remains the same. How was Einstein’s theory shown to be true?
What Did You Learn?
Give two examples of how one form of energy can change into heat energy. Give another example of an energy change.
List two ways in which energy does work for us.
The following list contains examples of forces, properties of matter, and forms of energy.

When physical systems interact, energy is converted into many different forms, but its total quantity always remains constant. The conservation of energy implies that the total output of all energy flows and transformations must equal the total input.
Energy flows among different systems represent the engine of the cosmos, and they happen everywhere, so often that we hardly notice them. Heat naturally flows from warmer to colder regions, hence our coffee cools in the morning. Particles move from high-pressure areas to low-pressure areas, and so the wind starts to howl. Water travels from regions of high potential energy to regions of low potential energy, making rivers flow. Electric charges journey from regions of high voltage to regions of low voltage, and thus currents are unleashed through conductors. The flow of energy through physical systems is one of the most common features of nature, and as these examples show, energy flows require gradients—differences in temperature, pressure, density, or other factors. Without these gradients, nature would never deliver any net flows, all physical systems would remain in equilibrium, and the world would be inert—and very boring. Energy flows are also important because they can generate mechanical work, which is any macroscopic displacement in response to a force.6 Lifting a weight and kicking a ball are both examples of performing mechanical work on another system. An important result from classical physics equates the quantity of work to the change in the mechanical energy of a physical system, revealing a useful relationship between these two variables.7
Although energy flows can produce work, they rarely do so efficiently. Large macroscopic systems, like trucks or planets, routinely lose or gain mechanical energy through their interactions with the external world. The lead actor in this grand drama is dissipation, defined as any process that partially reduces or entirely eliminates the available mechanical energy of a physical system, converting it into heat or other products.8 As they interact with the external environment, physical systems often lose mechanical energy over time through friction, diffusion, turbulence, vibrations, collisions, and other similar dissipative effects, all of which prevent any energy source from being converted entirely into mechanical work. A simple example of dissipation is the heat produced when we rapidly rub our hands together. In the natural world, macroscopic energy flows are often accompanied by dissipative losses of one kind or another. Physical systems that can dissipate energy are capable of rich and complex interactions, making dissipation a central feature of the natural order.

In the case of a weight that has been lifted from the ground, the weight has potential energy because if you let go of it, gravity will take over and cause the weight to move, towards your foot, and unless you move out of the way all of that newly acquired kinetic energy on the weight will transfer itself right into your toes. A simple equation for potential energy due to gravity, adequate for our purpose, is E = m * g * h, where m is the mass of the object, g is standard gravity (9.8 m/s² on Earth) and h is the height above the ground at which the object is at rest.
Knowing these two facts, can you see why running does no work? There is no change in potential energy unless you are running uphill, and we assume you are running on a fairly level surface such as a track, or a flat sidewalk. There is also no change in kinetic energy. You are both the observer and the body in question; your kinetic energy (motion) relative to yourself is always zero.
This doesn’t mean you should stop running! Despite the fact that no measurable net work is being done, you are still burning calories, strengthening your legs and your cardiovascular system, and boosting your metabolism.
Regarding exercises where work is done, but we still say zero: If you want your custom exercises given a proper work formula, give us a full, proper description of the movement (maybe a video as well, gym admins will be able to tag videos to exercises in the near future) and when we get the chance, we can come up with a formula and add it to the site. This will affect workout sessions posted in the past as well as the future, so go ahead and use any exercises you want in your workouts; when we know how to calculate the work done, your older sessions will show every ft-lb of work you did.
If you want to find out more about physics and Crossfit listen or read anything Coach Glassman has authored, and browse through the other great Crossfit Journal Articles. It’s where we started and continue to go for inspiration. Below are some CFJ articles to get you going.
- Force, Distance and Time
- Speech To Okinawa Marines
- Fit Fest 09
- ASEP Lecture
- Back Squat Geometry
- Ergometer Scores and Hall of Fame Workouts

Negative kinetic energies are not represented on the graph, and are shown with a zero line instead, because they are physically impossible.
Click the "Animate" button. The cart begins to move to the right from its initial position, with a speed that is determined from its kinetic energy and mass. The cart reaches a turning point when its kinetic energy becomes zero, it momentarily stops and reverses direction. At this point the graphs also redraw automatically. If there is friction, the total energy line (red) in the middle graph, is now slanted to the left, when the cart is moving to the left. The kinetic energy graph (bottom) also changes, to reflect the loss in kinetic energy. The ends of the cart are treated like elastic bumpers, and the cart bounces off them with no loss of energy. If the cartís kinetic energy becomes zero everywhere (due to loss to friction), it then stops moving.Direct comments to: Chandima Cumaranatunge (programming aspects); Sanjay Rebello (physics content).

It disappears from region B and appears in region E. Furthermore, we can also say that the momentum that flows from B to E is the negative of the momentum that flows the other way, from E to B. That’s just two ways of saying the same thing.
The flow from E to B is not in addition to the flow in the other direction. There is only one flow. The point is that we have several different sets of words for describing the same flow. Some momentum is disappearing from region B and appearing in region E.
If we translate this idea to the language of forces, we get the third law of motion: The force that B exerts on E is equal-and-opposite to the force the E exerts on B. So we see that the third law of motion is a corollary to the law of conservation of momentum. Expressing the idea in terms of conservation is slightly more powerful.
Of course there can be other forces, i.e. other momentum-flows, such as a flow from B to A or from B to C. However, if we restrict attention to the direct interaction between B and E, conservation tells us that whatever momentum crosses the boundary from B to E must simultaneously be lost from B and gained by E. This is absolutely exact, guaranteed.
Suppose we are interested in the dynamics of region B. Common sense tells us that to solve the whole problem, we need to calculate the entire force on the region. We need to calculate the entire momentum-flow into the region. This is as it should be. On the other hand, there is a proverb that says a journey of 100 miles begins with a single step. In many cases, there is a tactical advantage to calculating the momentum flow across some small part of the boundary of region B, such as the part that abuts region E. The conservation idea can help us do this part of the calculation. During this step, we should not allow ourself to be distracted by what’s going on elsewhere. Later, we can repeat the process for all other parts of the boundary.

Then:
But , and solving for
Step 5 : Now we have simplified as far as we can, we move onto momentum conservation:
But =0, and solving for
Step 6 :
Now we can substitute (B) into (A) to solve for :
We were lucky in this question because we could factorise. If you can't factorise, then you can always solve using the formula for solving quadratic equations. Remember:
So, just to check:
Step 7 :
So finally, substituting into equation (B) to get :
But, according to the question, marble 1 is moving after the collision. So and . Therefore:
An inelastic collision is a collision in which total momentum is conserved but total kinetic energy is not conserved
the kinetic energy is transformed into other kinds of energy.
So the total momentum before an inelastic collisions is the same as after the collision. But the total kinetic energy before and after the inelastic collision is different. Of course this does not mean that total energy has not been conserved, rather the energy has been transformed into another type of energy.
As a rule of thumb, inelastic collisions happen when the colliding objects are distorted in some way. Usually they change their shape. To modify the shape of an object requires energy and this is where the missing kinetic energy goes. A classic example of an inelastic collision is a car crash. The cars change shape and there is a noticeable change in the kinetic energy of the cars before and after the collision. This energy was used to bend the metal and deform the cars. Another example of an inelastic collision is shown in the following picture.
Here an asteroid (the small circle) is moving through space towards the moon (big circle). Before the moon and the asteroid collide, the total momentum of the system is:
stands for and stands for and the total kinetic energy of the system is:
When the asteroid collides inelastically with the moon, its kinetic energy is transformed mostly into heat energy. If this heat energy is large enough, it can cause the asteroid and the area of the moon's surface that it hit, to melt into liquid rock! From the force of impact of the asteroid, the molten rock flows outwards to form a moon crater.
After the collision, the total momentum of the system will be the same as before.

Such shells usually contain a core of tungsten or uranium ("depleted uranium" from which the component used for producing nuclear power has been removed), very heavy metals whose high mass can also carry a great deal of kinetic energy.]
The conservation of momentum is different--it is purely mechanical.
The total momentum going (say) into a collision always equals the total momentum coming out of it--there is nothing else momentum can convert to. It is therefore something we can always rely on in a calculation. The momentum given by a rocket to its gas jet is always equal to the momentum which it itself receives, regardless of the details of the process.
The way momentum will be introduced here is through an actual example.
Here go into the lesson, the calculation of the recoil of a cannon.
Guiding questions and additional tidbits:
-- What is the momentum P of a mass m moving with velocity v?
--Does this depend on the direction of v?
Yes, momentum is a vector quantity. If all motions are along the same line, we can take vector character into account by giving momenta in one direction a (+) sign and in the opposite direction a (-) sign.
--State the important property of momentum.
In an isolated system, the sum of all momenta is conserved.
-- What is "an isolated system"?
A system with no forces acting on it from the outside.
--When you jump across a ditch, your body clearly has a momentum P = mv during the jump. It did not have that momentum earlier and does not have it afterwards. How can you then say that P is conserved?
When you jump, you brace your foot against the ground, so that the Earth, too, is part of the system. When your body takes off, an opposite and equal amount of momentum has been given to the Earth, and in principle the Earth actually moves back a tiny, unmeasurable amount. When you land, your momentum is given back to the Earth, and everything is as before.
--A 1500 kg car going at 40 km/hr smashes head-on into a 4500 kg truck going in the opposite direction at 20 km/hr. The cars end up locked together. In what direction does the wreckage move (initially), and how fast?
Let 1 denote the car, and let the + direction be the one in which it moved.
Let 2 denote the truck, moving in the - direction.

Electrical potential energy
Example: Ionization energy of the electron in a hydrogen atom.
Chemical potential energy
Example: fossil fuel like coal. The energy is only released when a chemical reaction takes place, ie burning it with oxygen.
Gravitational potential energy
Example: The water behind a dam.
What factors affect the amount of gravitational potential energy?
Weight and height of an object
Explain what happens to kinetic energy when the mass and speed of an object changes.
Kinetic energy also changes because the kinetic energy of an object depends on its mass and its speed. It is equal to half the mass multiplied by the square of the speed, multiplied by the constant ½.
List examples of different types of kinetic energy.
A car moving along a road has kinetic energy, Energy can be transferred from one object to another, such as when a rolling bowling ball transfers some of its kinetic energy to the pins and sets them in motion. Energy also transforms, or changes form. For example, the gravitational potential energy of a raised ram transforms to kinetic energy when the ram is released from its elevated position. And, when you raise a pendulum bob against the force of gravity, you do work on it. That work is stored as potential energy until you let the pendulum bob go. Its potential energy transforms to kinetic energy as it picks up speed and loses elevation.
Explain the law of conservation of energy.
Whenever energy is transformed or transferred, none is lost and none is gained. In the absence of work input or output, the total energy of a system before some process or event is equal to the total energy after.
Define thermal energy.
Energy resulting from the motion of particles. Thermal energy is a form of kinetic energy and is transferred as heat.
Newton?s first law of motion
Every object continues in a state of rest, or in a state of motion in a straight line at a constant speed, unless it is compelled to change that state by forces exerted on it.
Newton?s second law of motion
The acceleration produced by a net force on an object is directly proportional to the net force, is in the same direction as the net force, and is inversely proportional to the mass of the object.
Newton?s third law of motion
whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first object.
Newton?s First Law of Motion-
Examples: 1. when you play tug of war.

Recently I’ve had a couple of people contact me with some ideas for how to get “free energy” using buoyancy. I’ve also reviewed some ideas using motors and generators, and explained why I don’t expect them to work either. It’s maybe time to have a bit of a rant (again) about the difference between work and energy, and why I think that whereas Free Work may be attainable (and has been demonstrated), Free Energy is most unlikely to be shown.
Let’s start with the paradox. There is the principle of Conservation of Mass/Energy, and since mass and energy are equivalent via E=MC² then in a closed universe we can’t change the amount of “stuff” we’ve got (mass/energy) but whatever we do we will end up with no more and no less. If we then look at a normal physics explanation of a process, we are told that we start with X joules of energy and we can do a little less than X joules of work, and then we have no energy left. This obviously doesn’t agree with the aforementioned CoE (conservation of energy). We really have a semantics problem, since the words we are using are not adequate.
I’m going to separate the words out. We have two forms of energy here (kinetic and potential) and we also have work. Potential energy includes mass, energy that is stored in springs of some sort, gravitational potential (may be stored as mass, but I’ll skip that question for now) etc.. Kinetic energy is stored as things that are moving, so we include photons, moving masses and other unbound energy not stored as mass. Work is on the other hand a bit trickier. Whenever we do work, at the end of it things are just in a different configuration than before. Some work goes into kinetic energy (KE) and/or potential energy (PE), some of it is simply that a lump of stuff is a different shape or location. Hammering a lump of iron into a sword (or ploughshare) takes a lot of work, but at the end of it we have the same lump of iron in a different shape. Work is not a conserved quantity, and that is an important observation.

How to convert kinetic energy into good, old-fashioned heat energy. The First Law of Thermodynamics states that heat cannot simply be created. Energy must be transferred from one form to another.
We could really use your help!
- Moving your hands back and forth too rapidly, or with too much pressure may cause discomfort. Use caution to prevent rug burn.
Things You'll Need
- Two hands
- Cold environment

Have a nice day.
Is electrical energy produced? yes or no
Where does that energy come from? give your answer
If your answer is “from the moving air” then what is the difference between the air before going through the turbine and after it comes out of the turbine?
Momentum is reduced, not temperature.
If you won’t accept the difference between potential energy, and absolute energy values, or that velocity is only a relative measurement, not an absolute measurement like tenperature, then I cannot explain it to you.
Velocity is similar to potential energy in height with gravity. If I raise a rock above the ground, I have supplied potential energy. But I did not raise the temperature of the rock by lifting, nor will it cool as it crutches what it lands upon.
Velocity is the same way. It has no measurement accept in creation to something else. Temperature is an absolute value and needs no reference frame. Think of throwing a ball or throwing a ball from a moving truck and the again thrown inside a moving truck. You cannot relate the velocity to the object’s tempature.
nor will it cool as it crushes what it lands...
Velocity is the same way. It has no measurement accept in relation to something else.
“won’t accept the difference”
Of course velocity is relative, and temperature has an absolute zero but in thermodynamics it’s differences in temperature that you deal with.
Now answer the questions I posed. Here are the first two:
Is electrical energy produced by the turbine?
Where does that energy come from?
Say as much as you want but make sure you answer the questions.
Yes electrical energy is produced by the transfer of momentum of the air to the rotational force on the turbine.
The only effects on temperature are the friction of the moving surfaces and the inefficiencies of the wind turbine equipment. Both of these produce heat.
There is no drop in temperature.
I have been referring to the energy in the moving mass as potential energy in relation to the still frame of reference of the windmill.
A better term is kinetic energy. Momentum is the mass times the velocity. Work is the mass times acceleration (deceleration of the wind mass). Kinetic energy is 1/2 the mass times the velocity squared.
When the wind strikes the turbine blades, the momentum of the collision must remain the same. In reality it is less of a collision and more of a sliding pull.

- It is important to note that when measuring mechanical energy, an object is considered as a whole, as it is stated by Isaac Newton in his Principia: "The motion of a whole is the same as the sum of the motions of the parts; that is, the change in position of its parts from their places, and thus the place of a whole is the same as the sum of the places of the parts and thereore is internal and in the whole body."
- In physics, speed is a scalar quantity and velocity is a vector. In other words, velocity is speed with a direction and can therefore change without changing the speed of the object since speed is the numerical magnitude of a velocity.
- Wilczek, Frank (2008). "Conservation laws (physics)". AccessScience. McGraw-Hill Companies. Retrieved 2011-08-26.
- "mechanical energy". The New Encyclopædia Britannica: Micropædia: Ready Reference 7 (15th ed.). 2003.
- Newton 1999, p. 409
- "Potential Energy". Texas A&M University–Kingsville. Retrieved 2011-08-25.
- Brodie 1998, pp. 129–131
- Rusk, Rogers D. (2008). "Speed". AccessScience. McGraw-Hill Companies. Retrieved 2011-08-28.
- Rusk, Rogers D. (2008). "Velocity". AccessScience. McGraw-Hill Companies. Retrieved 2011-08-28.
- Brodie 1998, p. 101
- Jain 2009, p. 9
- Jain 2009, p. 12
- Department of Physics. "Review D: Potential Energy and the Conservation of Mechanical Energy" (PDF). Massachusetts Institute of Technology. Retrieved 2011-08-03.
- E. Roller, Duane; Leo Nedelsky (2008). "Conservation of energy". AccessScience. McGraw-Hill Companies. Retrieved 2011-08-26.
- "James Prescott Joule". Scientists: Their Lives and Works. Gale. 2006. as cited on "Student Resources in Context". Gale.

There’s some logic there, in that if something is moving then we should be able to make it do some work, but in the case of ZPE I suspect it’s a problem of how we measure things and that that that energy is not actually available but is instead imaginary. Just because we measure something to be in a slightly different position does not mean that it’s actually moved, but that since our measurements require us to use some sort of particle to hit the thing we can’t really be totally sure of the measurements. There’s an underlying uncertainty of where the fundamental particle actually is, which is a probability function. ZPE therefore seems to me extremely unlikely to be a source of new energy and thus to break CoE.
With mechanical systems such as the motor/generators, gravity/buoyancy machines or electromagnetic systems, we start by putting some work in to get it going. That work gets stored somewhere as either KE or PE, and if we get work out of the machine then the available stored KE and PE reduces until it reaches zero and the machine stops. An equivalent system would be a bath full of water, where you think that if you pour in a glass of water to make it overflow then you’ll get a continuous stream of water out. It doesn’t happen – you just get a glassful out and then it stops overflowing. You can’t get more energy out than you put in.
So far I’ve trashed pretty well all of the “traditional” Free Energy systems as being non-workable. All is not lost, though, since I’ve pointed out that work is not a conserved quantity. Since I’ve also pointed out that work can be subdivided into stored KE, stored PE and displacement, and it should be pretty obvious that a simple displacement is a zero-energy transaction, there is however a chance that we can get the displacement-type work (which is often what we want) for free. That displacement is a zero-energy transaction has been known since Newton, since he said that a body in motion would continue in that motion unless there was a force acting. So – if you lift something up you’ve put in work which is stored as gravitational potential energy, and if you put it down again you can get that energy out again as work, but if you move it sideways then no work is done except against friction, and that can be reduced arbitrarily asymptotic to zero.

The effects of increasing entropy are unavoidable, and one important result of this fact is that in everything we do, there will always be some energy lost to entropy. For example, when an engine is running, it will always experience some friction in its mechanisms. Friction involves collisions between particles (as I’ve already mentioned), and so the particles involved tend to heat up, much like what happened with the bucket of warm water in a cool room. So the engine is only trying to push some pistons, but along the way it also transfers some heat energy into the metal, which then spreads out into the air around the engine. In other words, it ‘loses’ some of its energy in the form of heat.
We try to reduce the amount of friction in the engine using lubricants, but we can never avoid it entirely. Again, heat production is an example of an increase in entropy, which always tends to happen. And in any system we develop which uses energy to do some kind of work, there will always be some similar kind of entropy increase. Thus, no process can ever be 100% efficient.
I’d like to end this section with a short parable about energy use and entropy. Imagine that you live in an imaginary world where money can’t always buy you the things you need. And you want to build a platform that can lift people up a short cliff – in other words, an outdoor elevator. Your first idea is to build a simple pulley system and have your friends at the top of the cliff pull the ropes. This works fine for a few minutes, but it’s a popular cliff, and pretty soon you find that you don’t have enough food to feed your friends so that they’ll have enough energy to pull the ropes. In order to feed them, you’d have to plant fields, harvest grains, and then cook meals every day.
Luckily, you come up with a way around this problem: you tell your friends to tie big, heavy boulders to the other end of the rope. The boulders will fall, and the elevator will go up. Easy! What you have done is converted the gravitational potential energy of the boulders into kinetic energy as the system moved. Then, that kinetic energy turned back into gravitational potential energy for the elevator and its riders.

This implies that food input is in the form of work. Food energy is reported in a special unit, known as the Calorie. This energy is measured by burning food in a calorimeter, which is how the units are determined.
Can You Break The First Two Laws Of Thermodynamics
To break the first law of thermodynamics, wed have to create a “perpetual motion” machine that worked continuously without the input of any kind of power. That doesnt exist yet. All the machines that we know receive energy from a source and transform it into another form of energy. For example, steam engines convert thermal energy into mechanical energy.
To break the first law of thermodynamics, life itself would have to be reimagined. Living things also exist in concordance with the law of conservation of energy. Plants use photosynthesis to make food and animals and humans eat to survive.
Eating is basically extracting energy from food and converting it into chemical energy which is what actually gives us energy. We turn that chemical energy into mechanical energy when we move, and into thermal energy when we regulate our bodys temperature, etc.
But things may be a bit different in the quantum world. In 2002, chemical physicists of the Australian National University in Canberra demonstrated that the second law of thermodynamics can be briefly violated at the atomic scale. The scientists put latex beads in water and trapped them with a precise laser beam. Regularly measuring the movement of the beads and the entropy of the system, they observed that the change in entropy was negative over time intervals of a few tenths of a second.
This is a real-life demonstration of Maxwell’s demon, a thought experiment to break the second law of thermodynamics.
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First Law Of Thermodynamics Definition
|Working Of A Thermal Power Station Is Based On 1st Law Of ThermodynamicsCredit: Wikimedia Commons|
The First Law Of Thermodynamics is one of the Physical Laws Of Thermodynamics that states that heat is a form of energy and the total energy of a system and its surrounding remained conserved or constant. Or in more simple terms, for an isolated system energy can neither be created nor be destroyed. It can only be converted from one form of energy to another. Thats why the 1st law of thermodynamics is also known as the Law Of Conservation Of Energy.

Kinetic Energy - Energy in Motion
Energy which an object processes due to its motion is called Kinetic Energy and to explain further it is work done to accelerate a body of given mass from rest to its current or desired velocity, "KE" represent Kinetic Energy. This online calculator has been developed to calculate KE.
To calculate Power with Velocity:
What you want to calculate

1.3. Conservation of momentum and energy?
Are total momentum and energy conserved in cosmology? This is a nontrivial question because the canonical momentum and Hamiltonian differ from the proper momentum and energy.
Consider first the momentum of a particle in an unperturbed Robertson-Walker universe. With no perturbations, = 0 so that Hamilton's equation for p becomes dp / d = -am = 0, implying that the canonical momentum p is conserved. But, the proper momentum mv = a-1p measured by a comoving observer decreases as a increases. What happened to momentum conservation?
The key point is that v = dx / d is measured using a non-inertial (expanding) coordinate system. Suppose, instead, that we choose v to be a proper velocity measured relative to some fixed origin. Momentum conservation then implies v = constant (if = 0, as we assumed above). At = 1 and 2, the particle is at x1 and x2, respectively. Because dx / d gives the proper velocity relative to a comoving observer at the particle's position, at 1 we have dx / d = v - (/a)1 x1, while at 2, dx / d = v - ( / a)2 x2. (The proper velocity relative to the fixed origin is v in both cases, but the Hubble velocity at the particle's position - the velocity of a comoving observer - changes because the particle's position has changed.) Combining these, we find [(2) - (1)] / (2 - 1) - ( / a)[x(2) - x(1)] / (2 - 1) + O(2 - 1) or, in the limit 2 - 1 0, d2x / d2 = - (/a) dx / d. This is precisely our comoving equation of motion in the case = 0. Thus, the "Hubble drag" term ( / a)dx / d is merely a "fictitious force" arising from the use of non-inertial coordinates. Stated more physically, the particle appears to slow down because it is continually overtaking faster moving observers.
Energy conservation is more interesting. Let us check whether the Hamiltonian H(x, p, ) is conserved.

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quiz-energy forms and transfers
energy due to motion
energy stored in and released from the nucleus of an atom
energy stored in and released from the bonds between atoms
the sum of the potential energy and kinetic energy in a system
the sum ofthe kinetic energy and potential energy of the particles that make up an object
the energy carried by electromagnetic waves
sound is a form of energy carried by
what factors determine how much gravitational potential energy an object has?
mass and height
Law of conservation of energy states that energy can be __________________, but it cannot be created or destroyed
A system that exchanges matter or energy with the environment is _____________ system
wind energy is an example of a ___________ energy resource
A movement of energy from one object to another without a change in the form of energy is called
an example of energy transformation
chemical energy in a log changes to thermal energy when the log burns
an example of work
a bat hits a baseball to an outfielder
example of a nonrenewable resource

Hello everybody. Imagine a box in which two spheres are separated by some distance. nothing is moving inside. Einsteins E=m*c^2 must be always valid. Since nothing moves the energy of box is E=m°*c^2 where m° is rest mass. Since the spheres exert gravitational force on each other they will be ruching towards each other after some time. just before the collison the energy of box is E=m*c^2 and it is higher than previous energy since the motion os spheres has increased their mass and made it m. Now you can see that law of conservation of energy is violated although no energy is given/take out of system. Thinking of this experiment I could not find the answer to the question, JUST WHERE DOES THE POTENTIAL ENERGY FIT IN THE E=MC^2 EQUATION ? OR DOES IT AT ALL ?

Furthermore, the piston moved, thus a work is created. (Answer: Energy transfer is from the engine cylinder to the piston; Heat and Work)
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Arguably conservation of momentum and the principle of Galilean invariance are one and the same principle.
Whereas stating conservation of kinetic energy is very common the following property seems to be somewhat overlooked: kinetic energy is Galilean invariant. It's a necessary property: if kinetic energy would not be galilean invariant calculations would run into inconsistencies.
If kinetic energy is galilean invariant it must be possible to derive the conservation of kinetic energy from the invariance principles. So let's try that.
Let the total kinetic energy be called Ek. Kinetic energy is ½mv2, but I have omitted the ½ because here it's non-essential. Then we have the following expression for the kinetic energy before the collision. (The symbol ∝ means 'is proportional to'.)
Because of the minus sign quite a few terms drop away against each other. After that cleanup the expression regroups as follows:
After the collision
From symmetry it's immediately clear that in the expression for the total kinetic energy after the collision the same terms will drop away against each other, so after the cleanup and regrouping the expression will be the same as above.
There is the following limitation: while the derivation shows that there will be a conserved quantity that is proportional to the masses involved and to (Vr)2, it doesn't go beyond that; it doesn't single out a particular expression for Ek.
It's interesting to see how readily the total kinetic energy can be separated into independent contributions: a component that correlates to the relative velocity (Vr) of two objects, and a component that correlates to their common velocity (Vc) with respect to some reference. This shows that kinetic energy satisfies Galilean invariance: the amount of kinetic energy that is involved in the collision process depends only on the relative velocity between the two objects.
Momentum and kinetic energy
What is the relation between momentum and kinetic energy?
Given that the corresponding conservation laws are both derivatives of the time symmmetry and Galilean invariance it appears that momentum and kinetic energy must in some sense be two sides of the same coin.
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
Last time this page was modified: July 05 2015

The kinetic energy of a body moving with a certain velocity is equal to the work done on it to make it acquire that velocity.
Let us consider an object of mass m,moving with a uniform velocity u.Let it be displaced through a distance S.
When a constant force F acts on it in direction of its displacement.
Work Done= Force* Distance
The work done on the object will cause a change in its velocity.Let its velocity changes from u to v.Let a be the acceleration produced.
The relation connecting the initial velocity(u) and final velocity(v) of an object moving with a uniform acceleration(a) and displacement,S,is
v2 – u2 =2aS
v2 – u2
———- = S
From Newton’s Second law of motion
v2 – u2 m
———- * —– = S
W= m (v2 – u2 )
If the object is starting from its stationary position ie u=0,then
W=— m v2
Kinetic energy= —– m v2
Thus,kinetic energy possessed by an object of mass m,and moving with uniform velocity,v, is
KE = —– m v2
Kinetic energy is directly proportional to mass of body and square of velocity of body.
If mass of a body is doubled,its kinetic energy also gets doubled and if mass of body is halved,its kinetic energy al get halved.
If the velocity of body is doubled,its kinetic energy,becomes four times.
If the velocity of body is halved,then its kinetic energy becomes one-forth.
Heavy bodies moving with high velocities have more kinetic energy than slow moving bodies of small mass.
A brick lying on the ground.It has no energy so it cannot do any work.
Let us lift this brick to the roof of a house.Some work has been done in lifting this brick against the force of gravity.This work gets stored up in the brick in the form of potential energy.
The energy of a brick lying on the roof of a house is due to its higher position wrt ground.
Elastic potential energy is due to change in the shape of body.It can be brought about by compressing,bending or twisting.some work has to be done to change the shape of a body.
The energy of a body due to its position or change in shape is called potential energy.
When you stretch a rubber band,energy transferred to band is its potential energy.

To prove my point, lets look at a 'table' comparing KE, GPE, and the total energy of the system (which I will denote, W). http://xs72.xs.to/pics/06115/table.png [Broken] Note that in all cases, the total energy (W) of the system is 500 J at all times. The KE and the GPE fluctuate. Examine the change from Point A to Point B. The change in KE from Point A to Point B is (150 J - 0 J) = 150 J The change in GPE from Point A to Point B is (350 J - 500 J) = -150 J Based on the formula: dKE = -dGPE 150 J (dKE) = -(-150 J) (dGPE) 150 J = 150 J, thus energy is conserved. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= I hope by now you understand energy and I sure hope this topic is stickied as it is the best explanation you will ever find.

Why is matter not being created at the present time, nor being destroyed?
Matter is being created and destroyed now. For example, a high energy X-ray can collide with the nucleus of an atom and disappear and two particles, an electron and an anti-electron (a.k.a. positron), will appear in its place. So extra matter is being produced from no matter. The important thing is that the amount of total energy stays the same, but the energy can change its form from electromagnetic radiation (the X-ray) to matter (the electron and positron). Also, an electron and positron can collide with and annihilate each other, producing X-rays.
Mac Mestayer, Staff Scientist (Other answers by Mac Mestayer)

Question 1 Calculate the kinetic energy of a body of mass 2 Kg moving with a velocity of 0.1 m/s?
Question 2 How much work should be done on a bicycle of mass 20Kg to increase its speed from 2m/s to 5m/s?
Question 3 What are the various forms of energy?
Question 4 What do you understand by kinetic energy of a body?
Question 5 Write an expression for the kinetic energy of a body of mass m moving with velocity v?
Question 6 How does kinetic energy depends on its mass and velocity?
Question 7 If the speed of a body is halved,what will be the change in its kinetic energy?
Question 8 A ball of mass 200g falls from a height of 5 m.What is its kinetic energy when it just reaches the ground?
Question 9 Find the momentum of a body of mass 100 g having kinetic energy of 20J?
Question 10 What is the kinetic energy of a body of mass 1 kg moving with speed of 2m/s?
Question 11 What is potential energy?
Question 12 Is potential energy a scalar quantity or vector quantity?
Question 13 On what factors does the potential energy of a body depends?
Question 14 Give example where body possesses kinetic energy?
Question 15 What happens to the potential energy when height is doubled?
Question 16 A body of mass 2 Kg is thrown vertically upwards with an initial velocity of 20m/s.What will be its potential energy at the end of 2sec?
Forms of Energy
Kinetic energy,Potential energy,Chemical energy,Heat energy,Light energy,Sound energy,Electrical energy,Nuclear energy.
The energy of a body due to its motion is called kinetic energy.
Ex:1)A moving cricket ball can do work in pushing back the stamps.
2)Moving water can do work in turning the turbine for generating electricity.
3)Moving wind can do work in turning the blades of wind mill.
4)A moving hammer drives a nail into wood because of its kinetic energy.
5)A moving bullet can penetrate even a steel plate.
6)A moving bus,car,falling stone possesses kinetic energy.
7)A falling coconut,running athlete possesses kinetic energy.
The kinetic energy of a moving body is measured by the amount of work it can do before coming to rest.

Quantity of motion
Momentum and kinetic energy have in common that they are a measure of quantity of motion.
We take the following two postulates:
- Time-reversal symmetry for perfectly elastic collision
- Galilean invariance
Time reversal symmetry
When two objects of equal mass approach each other with equal velocity, and they collide with perfect elasticity, then their velocities will be reversed. That was a principle that from the 17th century on scientists relied upon in thinking about physical processes. Nowadays we have movie camera's, and we can play movies in reverse. We can readily see that in the case of a collision with perfect bounce we cannot discern whether the movie is being played forward or backward; perfectly elastic collision is symmetric in time.
(17th century scientists saw proof of the time-reversal symmetry in collision experiments. For instance, the case of two pendulums side by side so that when hanging still the bobs just touch. Then when both bobs are released from the same height, moving towards each other, they bounce back to the same height as the height they were released from. Of course, in coming to these conclusions the scientists had to assume that the small discrepancies they saw were due to friction only.)
To be a powerful set of principles the time-reversal symmetry must be paired with the principle that was introduced by Galilei, which nowadays is called 'Galilean relativity'. Imagine a set of large boats, all sailing along on perfectly smooth water. Each boat has a uniform velocity, all boats have some velocity relative to the other boats of the set. Then any experiment conducted onboard any of those boats will find the same laws of motion.
The 17th century scientist Huygens pointed out the following procedure: if you want to calculate the outcome of any collision, then transform to the coordinate system that is co-moving with the common center of mass, reverse the velocities and then transform back to the original coordinate system.
A more challenging case is where the mass of the two objects is unequal.
Common Center of Mass
In statics the Common Center of Mass (CCM) is an equilibrium point. Let two objects, with unequal mass, be connected by a stick with length L (for simplicity regard the stick as massless). Somewhere along the stick there will be an equilibrium point.

It is a scalar quantity that is measured in Joules (Newton meters in SI units) which can be defined as:
Work done= F×s×cosθ
Where F is the force applied to the object, s is the displacement of the object and cosθ is the cosine of the angle between the force and the displacement. In a linear example (with the force being exerted in the same direction as the displacement), the cosθ is equal to 1 and the equation simplifies to .
Example calculation: If a force of 20 newtons pushes an object 5 meters in the same direction as the force what is the work done?
F= 20 N s=5 m W=F×s=20×5= 100 J 100 Joules of work is done
Examples (when is work done?):
Force making an object move faster (accelerating) Lifting an object up (moving it to a higher position in the gravitational field) Compressing a spring
When is work not done
When there is no force Object moving at a constant speed Object not moving
Some useful equations;
If an object is being lifted vertically the work done to it can be calculated using the equation
Work done= mgh
Where m is the mass in kilograms, g is the earth's gravitational field strength (10N kg-1), and h is the height in meters
Work done in compressing or extending a spring
Work done = ½ kx2
Where k is Hooke's constant and x is the displacement
Energy and Power
Energy is the capacity for doing work. The amount of energy you transfer is equal to the work done. Energy is a measure of the amount of work done, this means that the units for energy and work must be the same- joules. Energy is like the "currency" for performing work. To do 100 joules of work, you must expend 100 joules of energy.
Conservation of energy
In any situation the change in energy must be accounted for. If it is 'lost' by one object it must be gained by another. This is the principle of conservation of energy which can be stated in several ways:
- The total overall energy of a closed system must be constant
- Energy is neither created or destroyed, it just changes form.

- there is no change in the total energy of the universe
Energy can be in many different types these include:
- Kinetic energy, Gravitational potential energy, Elastic potential energy, Electrostatic potential energy, Thermal energy, Electrical energy, Chemical energy, Nuclear energy, Internal energy, Radiant energy, Solar energy, and light energy.
You will need equations for the first three
- Kinetic energy = ½ mv2 where m is the mass in kg, v is the velocity (in ms-1)
- Gravitational potential energy= mgh where m is the mass in kg, g is the gravitational field strength, and h is the change in height
- Elastic potential energy =½ kx2 where k is the spring constant and x is the extension
Power -measured in Watts (W) or Joules per second (Js-1)- is the rate of doing work or the rate at which energy is transferred.
Power= energy transferred÷time taken= energy transferred÷time taken
If something is moving at a constant velocity v against a constant frictional force f, the power P needed is P= fv
If you do 100 joules of work in one second (using 100 joules of energy), the power is 100 watts.
Efficiency is the ratio of useful energy to the total energy transferred .
The change in the kinetic energy of an object is equal to the net work done on the object.
This fact is referred to as the Work-Energy Principle and is often a very useful tool in mechanics problem solving. It is derivable from conservation of energy and the application of the relationships for work and energy, so it is not independent of the conservation laws. It is in fact a specific application of conservation of energy. However, there are so many mechanical problems which are solved efficiently by applying this principle that it merits separate attention as a working principle.
For a straight-line collision, the net work done is equal to the average force of impact times the distance traveled during the impact.
Average impact force x distance traveled = change in kinetic energy
If a moving object is stopped by a collision, extending the stopping distance will reduce the average impact force.
Uniform Circular Motion (2.6)
The centripetal force with constant speed , at a distance from the center is defined as:

Scientists predicted this process in the 1930s, but it has never been achieved in a single direct step.
Where does matter and energy come from?
The Big Bang. Everything we know in the universe – planets, people, stars, galaxies, gravity, matter and antimatter, energy and dark energy – all date from the cataclysmic Big Bang.
Can something be created from nothing?
Something can be created from nothing
But such a perfect vacuum may not exist. One of the foundations of quantum theory is the Heisenberg uncertainty principle. It begins to be of profound importance to our understanding of nature at the atomic scale and below.
Are humans made of energy?
The molecules present in the cell are made up of basic elements such as carbon, oxygen, hydrogen, and nitrogen. These elements possess energy; hence we can say that humans are made of energy.
Can matter be destroyed?
Matter makes up all visible objects in the universe, and it can be neither created nor destroyed.
Do black holes destroy matter?
Specifically, as we understand it now, if you fall into a black hole you are guaranteed to hit the center, which is called the singularity. At the singularity you would be crushed into a ball of almost infinite density, which would destroy anything, even atoms, protons, or quarks.
Is antimatter a real thing?
Although it may sound like something out of science fiction, antimatter is real. Antimatter was created along with matter after the Big Bang. But antimatter is rare in today’s universe, and scientists aren’t sure why.
Can space be created or destroyed?
No. And nor is energy. Energy is the one thing we can neither create nor destroy, and it seems to be intimately related to what space is. But nevertheless the stress-ball does get bigger as the pressure reduces, so it’s reasonable to say space is “created”.
How was space time created?
Until the 20th century, it was assumed that the three-dimensional geometry of the universe (its spatial expression in terms of coordinates, distances, and directions) was independent of one-dimensional time. The physicist Albert Einstein helped develop the idea of spacetime as part of his theory of relativity.
Where does space time come from?
A quantum origin for spacetime.

Mechanical energy to heat energy: Rub a piece of sandpaper quickly over a board several times. Feel the sandpaper and the board. What kind of energy is produced?
Mechanical energy to sound energy: Remove the cover from a sturdy box and cut three groves on opposite edges of the box. Now choose three rubber bands of equal length, but each with a different thickness. Stretch the rubber bands around the box, fitting each into one of the grooves. Pluck each rubber band. Observe that it is vibrating. Listen for a sound. Repeat for each rubber band. Compare the pitch made by the different rubber bands. Record your observations.
The Science Stuff
Energy is what enables matter to move or to change. Energy is found in many different forms, such as heat, light, electricity, mechanical (the energy in moving things), sound, nuclear, and chemical. One form of energy can be changed into another form of energy. Still, the total amount of energy never changes. This means that energy cannot be created or destroyed. These ideas are expressed in one of the most important laws in all of science – the law of conservation of energy.
These activities illustrate some of the main forms of energy. Each activity shows one form of energy being changed into another form of energy. Electrical energy changed into light and heat, mechanical energy changed into heat, and mechanical energy changed into sound.
In the first activity, when the equipment was wired together correctly, an electric circuit was completed. An electric current then moved through the dry cell, wires, and light bulb. As the electric current moved through the light bulb, electric energy changed into light energy and heat energy.
This activity illustrates another important concept about energy. It shows that energy can be transferred from one place to another. Much of the earth’s energy is transferred from the sun to the earth.
Remember the conversation between Ella and her aunt? When Ella flipped the light switch, the electric current began to move through the wires and the light bulb. Inside the light bulb, electric energy changed into light and heat energy, which is the same thing that happened in your activity with electricity. When she turned the lights off, the objects in the room absorbed the heat and light energy. (This is a small amount of energy, and you probably couldn’t detect it without some sophisticated equipment.)
When you rubbed a board with sandpaper, your motion produced mechanical energy.

The kinetic force (energy ) from this event is said to have led to the extinction of the dinosaurs. Kinetic energy is the energy we get from an object in motion.
Fusion, or energy that comes when atom fuse, or combine, is what allows us to exist. This is what drives the stars. Our sun is using fusion to combine hydrogen and helium atoms together. In this process, energy in the form of radiation (Which becomes heat and light) is released. It is this energy from the sun that provides us with heat, light, and food on Earth.
Posted: Monday, February 29, 2016

In physics, the potential energy you talk about the most in mechanics is
gravitational potential energy. This is simply the potential energy caused by gravity.
Like if we take that same ball, and hold it off the side of the Empire State Building, it
has the "potential" of gaining a lot of kinetic energy (by dropping it). It has
a lot of potential energy, but no kinetic (it's not moving...yet.) But once you do, all
that potential energy will be converted to kinetic, not all at once, but gradually. The
ball speeds up faster and faster as it falls. A rule; the higher an object is, the more
gravitational potential energy it has.
Now you don't have to know anything I have just said to do good in chemistry, just take
away with you the Law of Energy Conservation. When you add the kinetic and potential
energies of that ball at any time during its fall, they will be the same. Energy can't be
gained or lost; it is always converted. Even when that ball hits the ground, and has lost
all its kinetic and potential energy, that energy didn't really die, it just got converted
to something else. The pavement (or car, wherever it landed doesn't matter) will have
gained a slight increase in temperature, and that's where the energy went. It was
dissipated as heat. The energy in a closed system always remains constant. I say
closed system because if you considered the Earth a closed system, and then an outside
source of energy (such as the falling of a great meteorite) came in, then the closed
system will have more energy.
Energy comes in all sorts of shapes and sizes. There's heat (probably most important
energy in chemistry), light, sound, mechanical, electrical, nuclear, matter/anti-matter
reactions, the list goes on...
Let's talk chemistry.
Chemistry 'n' Energy
Finally, back to chemistry. In chemistry, reactions can give off heat, or absorb heat.
Those that give off heat are called exothermic, and those that take in heat are
called endothermic.

In physics, energy (from the Greek ἐνέργεια - energeia, "activity, operation", from ἐνεργός - energos, "active, working") is a quantity that can be assigned to every particle, object, and system of objects as a consequence of the state of that particle, object or system of objects. Different forms of energy include kinetic, potential, thermal, gravitational, sound, elastic, light, andelectromagnetic energy. The forms of energy are often named after a related force. German physicist Hermann von Helmholtz established that all forms of energy are equivalent - energy in one form can disappear but the same amount of energy will appear in another form. Energy is subject to a conservation law. Energy is a scalar physical quantity. In the International System of Units (SI), energy ismeasured in joules, but in some fields other units such as kilowatt-hours and kilocalories are also used.
Because energy is strictly conserved and is also locally conserved (wherever it can be defined), it is important to remember that by the definition of energy the transfer of energy between the "system" and adjacent regions is work. A familiar example is mechanical work. Insimple cases this is written as the following equation:
ΔE = W (1)
if there are no other energy-transfer processes involved. Here E is the amount of energy transferred, and W represents the work done on the system.
More generally, the energy transfer can be split into two categories:
ΔE = W + Q (2)
Where Q represents the heat flow into the system.
There are other ways inwhich an open system can gain or lose energy. In chemical systems, energy can be added to a system by means of adding substances with different chemical potentials, which potentials are then extracted (both of these process are illustrated by fueling an auto, a system which gains in energy thereby, without addition of either work or heat). Winding a clock would be adding energy to a mechanicalsystem. These terms may be added to the above equation, or they can generally be subsumed into a quantity called "energy addition term E" which refers to any type of energy carried over the surface of a control volume or system volume.

Mass-energy equivalence[change | change source]
E=mc2, also called the mass-energy equivalence, is one of the things that Einstein is most famous for. It is a famous equation in physics and math that shows what happens when mass changes to energy or energy changes to mass. The "E" in the equation stands for energy. Energy is a number which you give to objects depending on how much they can change other things. For instance, a brick hanging over an egg can put enough energy onto the egg to break it. A feather hanging over an egg does not have enough energy to hurt the egg.
A cannonball hangs on a rope from an iron ring. A horse pulls the cannonball to the right side. When the cannonball is released it will move back and forth as diagrammed. It would do that forever except that the movement of the rope in the ring and rubbing in other places causes friction, and the friction takes away a little energy all the time. If we ignore the losses due to friction, then the energy provided by the horse is given to the cannonball as potential energy. (It has energy because it is up high and can fall down.) As the cannonball swings down it gains more and more speed, so the nearer the bottom it gets the faster it is going and the harder it would hit you if you stood in front of it. Then it slows down as its kinetic energy is changed back into potential energy. "Kinetic energy" just means the energy something has because it is moving. "Potential energy" just means the energy something has because it is in some higher position than something else.
When energy moves from one form to another, the amount of energy always remains the same. It cannot be made or destroyed. This rule is called the "conservation law of energy". For example, when you throw a ball, the energy is transferred from your hand to the ball as you release it. But the energy that was in your hand, and now the energy that is in the ball, is the same number. For a long time, people thought that the conservation of energy was all there was to talk about.
When energy transforms into mass, the amount of energy does not remain the same. When mass transforms into energy, the amount of energy also does not remain the same. However, the amount of matter and energy remains the same.

Krishnamurti: It is the same thing. Do we accept this that there is a beginning and ending of energy?
F: Individuals may begin and end, but life does not. It creates.
Krishnamurti: Do not bring in the individual yet. There is a movement of energy which is mechanical, which is measurable, which may end, and there is life-energy which you cannot manipulate; it goes on infinitely. We see that in one case there is wastage of energy and in the other there is non-wastage of energy.
F: I do not see the other as a fact.
Krishnamurti: All right. Let us see the movement of energy which can reach a height and decline. Is there any other form of energy which can never end, which is not related to the energy which begins, continues and withers away?
F: That is a legitimate question.
D: Is there any form of energy that will not decay?
Krishnamurti: Now how are we going to find out? I have got it. What is energy that decays?
F: What is the cause of energy you cannot answer.
Krishnamurti: What is energy that decays? I did not say what is the cause of energy.
P: Material energy decays. Why does it decay? By friction?
D: By pressure?
Krishnamurti: Is there any other form of energy which does not decay? One decays through friction. Is there any other form which does not decay?
P: Not only does it decay but it is friction. I am positing it. Let us investigate. Its very nature is friction.
F: No. I do not understand your method. The fact is that there is energy overcoming friction, and energy dissipating in friction.
P: You say there is an energy which decays in friction through friction. I say its very nature is friction. All that movement which we call energy, in itself is friction. Show me why it is not so?
F: What is friction?
P: Friction is contradiction, resistance.
F: Why should energy be identified with resistance?
P: We say the nature of this which we call energy is friction. D: Energy is the capacity, biological capacity, to overcome resistance, but it dissipates itself in this process.

Nuclear energy is interesting because when it operates, unlike burning coal or natural gas, it creates no pollution which might make you think it is a form of green energy. But the fuel that has been used to supply the atoms is highly radioactive and must be safely stored to avoid contamination of the environment. In addition, a nuclear reaction creates a lot of heat which is carried away by cooling water. If the supply of cooling water gets cut off from the reactor and the reaction continues, it becomes a very dangerous situation referred to as “meltdown” which can release deadly levels of radiation. Many people think that the “smoke” that they see coming from a nuclear power plant id radioactive. This is NOT the case. What you are seeing is water vapor from the water that was used to cool the reactor coming from the cooling towers. Some plants are built on lakes and actually transfer the heat to the lake itself. The sun is a large fusion reaction.
The second type of energy is kinetic energy or the energy of motion:
Kinetic Energy – is based on the motion of an object and is a function of how heavy the object is (its mass)and how fast it is moving, its velocity. If a 25 pound one year old child is running to jump on you, you’re probably not going to be too concerned and will let them hit you, but, if a 250 pound football player is running to jump on you, I suspect you’re going to try and move. This is because the energy of the impact will be 10 times higher for the football player moving at the same speed as the one year old. If I throw a b-b at you I don’t think you’ll be concerned, but if I shoot it from a b-b gun then you know it’s going to hurt. The b-b has very little mass but when given a lot of velocity and has a lot more energy. In fact, we would say it has exponentially more energy since velocity is squared in the formula for kinetic energy:
Kinetic Energy = ½ * m*v^2= ½ * mass * velocity^2
Water running in a river or stream, the motion of waves and the wind are all examples of naturally occurring kinetic energy. We use this natural kinetic energy to generate electricity by driving an electric generator. Wind Energy, Hydro (water) Energy and Wave Energy are all considered both green and renewable forms of energy.

Wave Motion - How it works
R ELATED F ORMS OF M OTION
In wave motion, energy—the ability to perform work, or to exert force over distance—is transmitted from one place to another without actually moving any matter along the wave. In some types of waves, such as those on the ocean, it might seem as though matter itself has been displaced; that is, it appears that the water has actually moved from its original position. In fact, this is not the case: molecules of water in an ocean wave move up and down, but they do not actually travel with the wave itself. Only the energy is moved.
A wave is an example of a larger class of regular, repeated, and/or back-and-forth types of motion. As with wave motion, these varieties of movement may or may not involve matter, but, in any case, the key component is not matter, but energy. Broadest among these is periodic motion, or motion that is repeated at regular intervals called periods. A period might be the amount of time that it takes an object orbiting another (as, for instance, a satellite going around Earth) to complete one cycle of orbit. With wave motion, a period is the amount of time required to complete one full cycle of the wave, from trough to crest and back to trough.
Harmonic motion is the repeated movement of a particle about a position of equilibrium, or balance. In harmonic motion—or, more specifically, simple harmonic motion—the object moves back and forth under the influence of a force directed toward the position of equilibrium, or the place where the object stops if it ceases to be in motion. A familiar example of harmonic motion, to anyone who has seen an old movie with a clichéd depiction of a hypnotist, is the back-and-forth movement of the hypnotist's watch, as he tries to control the mind of his patient.
One variety of harmonic motion is vibration, which wave motion resembles in some respects. Both wave motion and vibration are periodic, involving the regular repetition of a certain form of movement. In both, there is a continual conversion and reconversion between potential energy (the energy of an object due to its position, as for instance with a sled at the top of a hill) and kinetic energy (the energy of an object due to its motion, as with the sled when sliding down the hill.)

The energy conservation law is compatible with every single observation we have made inside the Milky Way in science, or outside science, so the empirical evidence in favor of it is overwhelming, diverse, and universal.
Theoretically, the case is also clear. Emmy Noether demonstrated that conservation laws are linked to symmetries. The validity of the energy conservation law is equivalent to the time-translational symmetry of the laws of physics: the same phenomena occur if one starts with the same initial conditions but just a bit later. This is true for the laws of mechanics, field theory, electromagnetism, nuclear interactions, classical physics, quantum mechanics, thermodynamics and statistical physics, special relativity. The energy conservation law is valid in all these situations and respected by all the major theories describing these subfields of physics.
Motors, those produced by Faraday, Tesla, or anyone else, as well as all other engines and objects in the Universe preserve the energy, too. And there exists no equivalence or analogy between the energy conservation law and the existence of Tesla's or Faraday's motor. In particular, there has never existed any solid evidence – empirical or theoretical – that electricity or magnetism couldn't do work. So any analogy between these totally different questions is an example of something technically referred to as demagogy. To create legitimate doubts about the validity of such an important and well-established law, one would need an observation or an arguments that actually discusses the technical properties of energy (and one would probably have to construct a viable theory disagreeing with the energy conservation law that is compatible with the observations) – rather than demagogic comparisons to completely different questions that the speaker desires to be answered by the same answer No although there doesn't exist a glimpse of a rational reason why the answers should be the same.
To see violations of the energy conservation law, one has to go to cosmology. However, due to the slow evolution of the Universe today, one needs to wait approximately for 10 billion years for the total energy of a system to change by an amount comparable to 100%. In the early stages of the cosmological evolution of our Universe, the total energy wasn't conserved – this is particularly important for cosmic inflation that created the energy of the whole Cosmos out of "almost nothing". But this non-conservation depended on the background spacetime's heavy violation of the time-translational symmetry.

- What is the energy of moving things called?
- What is the ability to make things move or change called?
- How can energy make things move?
- When work is done in the body gains?
- When work is done on a body its energy?
- Is it correct to say work is done every time force is applied?
- When one can say that work is done on the body?
- What is 1joule work?
- What does peak current mean?
Telekinesis, also known as Psychokinesis (PK) is simply the ability to move an object in some manner without coming into physical contact with it. In essence, it is the psychic ability to use the power of the mind to manipulate a specific target and conform it to your will.
What is the energy of moving things called?
Energy that a moving object has due to its motion is Kinetic Energy. Kinetic Energy: Is energy of motion.
What is the ability to make things move or change called?
Defining Energy Energy is defined in science as the ability to move matter or change matter in some other way. Energy can also be defined as the ability to do work, which means using force to move an object over a distance.
How can energy make things move?
Motion energy is the sum of potential and kinetic energy in an object that is used to do work. Work is when a force acts on an object and causes it to move, change shape, displace, or do something physical. Potential energy is energy that is stored in an object or substance.
When work is done in the body gains?
The total amount of work done on a body equals the change in its kinetic energy. Work done is said to be positive when an external force acts in the direction of motion of the body. If positive work is done on a body by an external force, then the body gains kinetic energy.
When work is done on a body its energy?
work done on body =change in kinetic energy of the body.
Is it correct to say work is done every time force is applied?
If a force is applied but the object doesn’t move, no work is done; if a force is applied and the object moves a distance d in a direction other than the direction of the force, less work is done than if the object moves a distance d in the direction of the applied force.
When one can say that work is done on the body?

Energy turns into mass and mass turns into energy in a way that is defined by Einstein's equation, E = mc2.
The "m" in Einstein's equation stands for mass. Mass is the amount of matter there is in some body. If you knew the number of protons and neutrons in a piece of matter such as a brick, then you could calculate its total mass as the sum of the masses of all the protons and of all the neutrons. (Electrons are so small that they are almost negligible.) Masses pull on each other, and a very large mass such as that of the Earth pulls very hard on things nearby. You would weigh much more on Jupiter than on Earth because Jupiter is so huge. You would weigh much less on the Moon because it is only about one-sixth the mass of Earth. Weight is related to the mass of the brick (or the person) and the mass of whatever is pulling it down on a spring scale — which may be smaller than the smallest moon in the solar system or larger than the Sun.
Mass, not weight, can be transformed into energy. Another way of expressing this idea is to say that matter can be transformed into energy. Units of mass are used to measure the amount of matter in something. The mass or the amount of matter in something determines how much energy that thing could be changed into.
Energy can also be transformed into mass. If you were pushing a baby buggy at a slow walk and found it easy to push, but pushed it at a fast walk and found it harder to move, then you would wonder what was wrong with the baby buggy. Then if you tried to run and found that moving the buggy at any faster speed was like pushing against a brick wall, you would be very surprised. The truth is that when something is moved then its mass is increased. Human beings ordinarily do not notice this increase in mass because at the speed humans ordinarily move the increase in mass in almost nothing.
As speeds get closer to the speed of light, then the changes in mass become impossible not to notice. The basic experience we all share in daily life is that the harder we push something like a car the faster we can get it going. But when something we are pushing is already going at some large part of the speed of light we find that it keeps gaining mass, so it gets harder and harder to get it going faster.

And if big-bang should somehow exist, why is there no free-energy now?
Gravity pulling objects in?
Does the sun move when the earth revolves around it? Is this movement immediate or does it
depend on the speed of light? If it is not immediate it would mean some energy is lost!
(just like the proton and electron example)
I'm no specialist in gravity to answer this question, but any answer is interesting.
Even if I look at the Higgs-field as a carrier of gravity the problem is similar.
According to my theory there must be some other phenomenon that compensates or prevents
this energy loss if it happens. Some kind of expansion maybe?
What about black-holes (if they exist), what is there to conserve energy?

As the gas cools, energy is delivered as propulsion (see the sections “Temperature” and “Euler’s equation”). We estimate the propulsion energy in 2 situations:
(1) duct, moving in a straight line;
First, write the conservation of linear momentum
and let delta t --> 0. We get the thrust equation
where Fext is an external force resisting the motion of the system, M_dot is negative because the system is losing mass as it moves and u is the velocity of the exiting gas w/respect to the stationary frame of reference. The second term is known as “thrust”. When u=0 and v=const=c we get an expression for the propulsion energy
(2) rotating duct.
First, write the conservation of angular momentum
and let delt t --> 0. We get the thrust equation
where tau_ext is an external torque due to the resistance of the surroundings; the second term in the Rhs represents rotational thrust; M_dot is negative since the system is losing mass during its motion. Again, if v=const=c the thrust is precisely counterbalanced by the external resistance and the propulsion energy turns out to be the same as above
This formula shows that a gaseous mass m, initially at rest in one frame of reference, makes the transition, at the expense of its own stagnation enthalpy, to a state of rest in another frame of reference, where the 2 reference frames move with respect to each other with constant linear velocity c. Thus, the above formula stems from the physics of a system with variable mass.
If we perform temperature analysis, the exact same formula comes out as the result. The released thrust energy is given through the decrease of total temperature
because, as we saw in the “Temperature” section of this site,
One can call the mc^2 formula an “apparent mass-energy equivalence”, since to an observer in the starting frame where m is initially at rest, it seems that the removal of this mass leads to the liberation of energy. In fact, the mass only transitions between 2 frames of reference and is not equivalent to energy. It releases some of its pressure and thermal energy in the transition.
The information contained in this site is based on the following research articles written by Jeliazko G Polihronov and collaborators:

Instead, I suggest that any inventor who believes he or she has a free-energy device build that device and demonstrate it openly for the physics community. Take it to an American Physical Society conference and present it there. Let everyone in the audience examine it closely. Since anyone can join the APS and any APS member can talk at any major APS conference, there is plenty of opportunity. If someone succeeds in convincing the physics community that they have a true free-energy machine, more power to them (no pun intended). But given the absence of any observed failure of time-translation symmetry, and therefore the steadfast endurance of energy conservation laws, I don't expect any successful devices.
You're both right about temperature being associated with kinetic energy in molecules: the more kinetic energy each molecule has, the hotter the substance (e.g. a person) is. But not all kinetic energy "counts" in establishing temperature. Only the disordered kinetic energy, the tiny chucks of kinetic energy that belong to individual particles in a material contributes to that material's temperature. Ordered kinetic energy, such as the energy in a whole person who's running, is not involved in temperature. Whether an ice cube is sitting still on a table or flying through the air makes no difference to its temperature. It's still quite cold.
Friction's role with respect to temperature is in raising that temperature. Friction is a great disorderer. If a person running down the track falls and skids along the ground, friction will turn that person's ordered kinetic energy into disordered kinetic energy and the person will get slightly hotter. No energy was created or destroyed in the fall and skid, but lots of formerly orderly kinetic energy became disordered kinetic energy—what I often call "thermal kinetic energy."
The overall story is naturally a bit more complicated, but the basic idea here is correct. Once energy is in the form of thermal kinetic energy, it's stuck... like a glass vase that has been dropped and shattered into countless pieces, thermal kinetic energy can't be entirely reconstituted into orderly kinetic energy. Once energy has been distributed to all the individual molecules and atoms, getting them all to return their chunks of thermal kinetic energy is hopeless. Friction, even at the molecular level, isn't important at this point because the energy has already been fragmented and the most that any type of friction can do is pass that fragmented energy about between particles.

But there are inefficiencies in your walking process that lead you to waste energy as heat in your own body. So the energy you convert from food energy to gravitational potential energy in climbing the stairs is fixed, but the energy you use in carrying out this procedure depends on how you do it. The extra energy you use mostly ends up as thermal energy, but some may end up as sound or chemical changes in the staircase, etc.
Actually, some bearings are dry (no grease or oil) and still last a very long time. The problem is that the idea touch-and-release behavior is hard to achieve in a bearing. The balls or rollers actually slip a tiny bit as they rotate and they may rub against the sides or retainers in the bearing. This rubbing produces wear as well as wasting energy. To reduce this wear and sliding friction, most bearings are lubricated.
If you brake your car too rapidly, the force of static friction between the wheels and the ground will become so large that it will exceed its limit and the wheels will begin to skid across the ground. Once skidding occurs, the stopping force becomes sliding friction instead of static friction. The sliding friction force is generally weaker than the maximum static friction force, so the stopping rate drops. But more importantly, you lose steering when the wheels skid. An anti-lock braking system senses when the wheels suddenly stop turning during braking and briefly release the brakes. The wheel can then turn again and static friction can reappear between the wheel and the ground.
When a ball bounces, some of its molecules slide across one another rather than simply stretching or bending. This sliding leads to a form of internal sliding friction and sliding friction converts useful energy into thermal energy. The more sliding friction that occurs within the ball, the less the ball stores energy for the rebound and the worse the ball's bounce. The missing energy becomes thermal energy in the ball and the ball's temperature increases.
Actually, both a mouse ball and a bowling ball will bounce somewhat if you drop them on a suitably hard surface. It does have to do with elasticity. During the impact, the ball's surface dents and the force that dents the ball does work on the ball—the force on the ball's surface is inward and the ball's surface moves inward. Energy is thus being invested in the ball's surface. What the ball does with this energy depends on the ball.

As I already wrote in a previous post, matter can be characterized as a
system that contains particles with non-zero rest mass
. Taking the simplest atom, viz. the hydrogen atom, as an example, this consists of a proton (that itself enjoys an internal structure by being composed of quarks that are held together by the exchange of gluons) and one electron, both interacting via the exchange of virtual photons. The latter are the messenger particles that convey the electromagnetic force; photons have zero rest mass, while the electron and the proton enjoy a nonzero rest mass. The mass of the latter is about 1840 times the mass of the former, so that most of the rest mass of the atom is concentrated in its nucleus.
Let me try to provide a bit more information to some statements in postings above:
Matter can neither be created or destroyed
No, that is not true. If matter and antimatter collide, e.g. hydrogen and antihydrogen (consisting of a (negatively charged) antiproton and a (positively charged) positron), then both annihilate into radiation, i.e., photons. However, the assertion above becomes correct if "matter" is replaced by "mass", so:
Mass can neither be created or destroyed
It is the motion of the electrons that creates the illusion of solid matter
. Well, this "motion" must be regarded as being very different from the orbiting of, e.g., planets around a central star. If the electrons in an atom were really moving, then (since they are charged particles) this would imply that they would constantly produce electromagnetic radiation, so atoms would lose energy by radiating all the time and thus couldn't be stable. Actually, the probability distribution of electrons in an atom is static and thus does not change in time (unless perturbed by "external" effects). It is the complex phase of the electronic wavefunction that oscillates in time. On the other hand, it is true that the kinetic energy of the electrons is required to render atomic systems stable. Without this kinetic energy, the electrostatic attraction between the positive nucleus and the negatively charged electrons would make the latter to collapse into the nucleus. The structure of atoms and molecules and thus of "ordinary" matter is also significantly influenced by the fact that electrons are fermions and thus the Pauli exclusion principle holds which forbids any two electrons to occupy the same quantum state.

The ice will melt, and eventually the glass of water will reach a state of equilibrium with the surrounding environment (it will stabilize at room temperature) at which point no potential difference in the field remains.
All field motion occurs as the energy field attempts to maintain equilibrium in field density. Ultimately the field must correspond to the distribution described by the inverse square law, however since the field is ‘quantized’ (it has become many fields) this result becomes impossible to achieve in practice, and the result is then perpetual field motion (the field becomes like Don Quixote, perpetually tilting at windmills). In the diagram above we illustrate the magnetic field and the electric field ‘forces’, which are at right angles to one another. The purpose of the magnetic field is to respond to changes in field density (potential differences) doing so in such a way as to achieve the desired final result of field equilibrium (what the field considers a correct density distribution of energy). The role of the electric field is to transfer energy within the field. You never have such a transfer of energy (a current) without a corresponding magnetic field being generated at the same time, and the reverse is also true, for wherever a magnetic field is present, currents of energy are on the move within a field.
The Hoover Dam
The Hoover Dam uses ‘momentum’ in the form of the motion of moving water allowed to fall down upon and spin electromagnetic turbine generators to generate electrical current, which is just momentum once again, this time in the form of flying electrons moving through a circuit in some wires (momentum having been transferred from a moving current of water to a moving current of electrons).
If you pick up a rock and then drop it on the ground, it will impact the ground and perhaps kick up a small cloud of dust. If you were to drop the same rock from very high in the atmosphere, the rock would begin to fall towards the surface of the earth, and the rock would be constantly accelerating as it descended. Finally the enormous velocity of the falling rock would generate so much air friction that the rock would burst into flames and then when hit impacted the surface it would generate an explosive impact. B y dropping the same rock from a high altitude it became a highly energetic, high velocity projectile.

Ultimately, all energy can be translated into an improbably concentrated (compacted) distribution (dance) of photons. I suspect that all the other manifestations of potential, kinetic, heat, chemical, radiation and etc energy are complex manifestations of this basic "photon into matter" compaction (see the section below entitled, "even wilder speculation here"). In quantum foam, there is a rapid (which equates to a very short distance) return to the "mean". The "mean" should be represented by utter nothingness – "nihil" – "zilch" – "non-existence" (a virtual state) with quantum foam lying close by on either statistical side. (Indeed, the uncertainty principle seems to encourage a boiling, yocto-scopic jitteriness either side of nothing. Note that micro-, nano-, pico-, fempto- yocto- are increasingly small. There is more on this general principle in the speculation section.)
Within the closed system of our theoretically perfect box, no energy is added or lost; our definition has proclaimed this. All that happens is that the energy is re-distributed evenly throughout the box so that no usable "macroscopic" PDs remain that are then available to be tapped for our wilful purposes. A useful illustration is to think of a box containing oxygen and a jar of diesel, both in matching quantities that will ensure complete combustion once the diesel is ignited. This initial system (effectively two isolated systems, oxygen and diesel, before ignition) has low entropy and remains in this state until it is ignited (at which point the low to high entropy flux begins). Now, all the diesel burns up reacting with all the oxygen. It now transforms into a state of high entropy where no new work can be "tapped" within the box because equilibrium has been reached and no workable PDs are left (even though the contents of the box are now much hotter). Similarly, 100ml of deuterium in a very large box represents a potential state of very low entropy (sometimes described as negentropy, though the qualifier high- or low- should also be added to this term) which, if a sustained fusion reaction could be initiated, would lead to a flow to a state of high entropy even though the contents of the box have become extremely hot and the pressure very high – or we have decreed that no energy flows out of our perfect system.

Yes, energy is a vector quantity. There is an energy component to everything. This is a vector quantity because we cannot measure the force of gravity. In physics, force is a vector quantity. A force is the product of a vector and a scalar quantity called the mass of a body. This is true of all of our actions. When we move a body, say a basketball, there is a force on it. We have a force on the basketball.
The weight of a body is the same as the mass of a body. If we are on a mountain, we have a force on the mountain. We do not have a force on the mountain. We have a force on a man. These are the same forces that we have on our enemies.
Energy is a vector quantity. This means that the magnitude of energy depends on the direction it is measured in. The energy of an object is proportional to its mass and the speed at which it moves. (For example, if your finger is moving at a speed of one foot per second then the energy of your finger will be one joule per second. If your finger moves at a speed of one foot per second then the energy will be one joule per second.
Energy is an important factor in the creation of an object. It’s the energy of the object itself creating the object. The energy of an object is the energy stored in the object. This is why objects with large amounts of energy can explode or explode with a destructive force. An object with a small amount of energy will probably disintegrate. The energy of a material that is created by a machine is the energy that goes into the machine itself.
The energy that is created by a machine is called’residual energy’.
Now, the energy of a material is not a vector quantity. It is not a momentum. It is not something that we think is really going to affect our lives and that we have to wait for it to get out of the machine. The energy of a material is the energy that gets released as the material is created. It is the energy that comes from the “maker” of the material.
The energy that is produced by a material is calledenergy storage. Energy storage is the electricity that is produced when a material is made by a machine. The energy storage of a material is calledcapacity. The capacity that is produced by a material is calledcapacity.

When no more potential difference exists between your rocket’s momentum field and the surrounding earth momentum field, the centrifugal force vanishes and you have lost all of your ‘conserved momentum’ and the time has come for the centripetal force to begin to do its job of getting your rocket properly sorted within a sorted mass field according to the requirements of the Inverse Square Law. Rockets are quite dense, unlike weather balloons and so therefore your rocket must be sorted somewhere below the surface of the earth. We suggest here that even a ‘mass field’ composed of matter must be sorted according to the rules of the Inverse Square Law (light helium at the top of the properly sorted field and dense iron somewhere below the visible surface of the earth).
Now once your rocket has come to a full stop the centripetal force will now begin to ‘sort’ the rocket according to density for the rocket will be found to be parked on the spot where a helium filled weather balloon is parked, which is the wrong place to park some rocket (this being a low density region of the mass field and a rocket, as we know, is much more dense than a helium balloon and therefore is parked on the wrong spot). The rocket then is pulled by this centripetal force to a lower region of the field, with higher density, which is where it belongs, and once again this happens at a certain fixed rate, one quanta of momentum energy at a time. At each step the rocket momentum field is brought into equilibrium with the density of the earth’s momentum field, which requires a transfer of momentum from the earth field to the rocket field.
We can see here that motion is the mechanism by which ‘transfer of momentum’ occurs and that motion and momentum transfer are therefore equivalent. This then leads us to draw the conclusion that ‘the so called law of the conservation of momentum’ is a myth for whenever motion is occurring through a gradient and constantly changing field, transfer of momentum quanta is occurring at the same time. In this way the momentum field of the rocket and the surrounding momentum field of the earth act like two cells of a battery and energy is in motion to constantly maintain field equilibrium.
Now someone might suggest that ‘conserved momentum’ is only impossible in some ‘gravity field’ this being due to the fact that gravity will suck the conserved momentum right out of some object.

This is almost always how we ...
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In this case mass is not conserved and the mass of an object is not the sum of the masses of its parts. Thus, the mass of a box of light is more than the mass of the box and the sum of the masses of the photons (the latter being zero). Relativistic mass is equivalent to energy, which is why relativistic mass is not a commonly used term nowadays.
Eating six meals per day will ensure that your body always has the nutrients it needs to repair and build more muscle. You will never be in starvation mode. I will be honest, eating six meals a day takes planning and dedication. However, not for Mark Boyle who has turned his life into a radical experiment. Mark Boyle was born in 1979 in Ireland and moved to Great Britain after Mark Boyle began to realise that many of the world's problems are just symptoms of a deeper problem. He thought that money gave people the illusion of...
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The more intensely and flawlessly his techniques duplicate empirical objects, the easier it is today for the illusion to prevail that the outside world is the straightforward continuation of that presented on the screen. This purpose has been furthered by mechanical reproduction since the lightning takeover by the sound film.
Dec 21, 2020 · A body has kinetic energy when it is in motion. If a body of mass m is moving at a velocity v, then: Kinetic energy = (1/2)mv 2. The kinetic energy of a body at velocity v is the work that must be done on the body to accelerate it to that velocity. Example: A rifle bullet of mass 4 grams is moving at a velocity of 1200 m/s. Calculate its energy. Momentum is inertia in motion.It is the product of an object's mass and its velocity . Which has more momentum? An 80,000 pound big rig traveling 2 mph or a 4,000 pound SUV traveling 40 mph? circle one Big Rig SUV same Soccer Kicks, Slap Shots, and Egg Toss What is it that changes an object's momentum? an impulse .It is the product of
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The boy and toboggan together have a mass of 50 kg, and the slope is at an angle of 30° to the horizontal.

However, the energy associated with rest mass is hard to release and only tiny fractions of it can be obtained through conventional means. Chemical reactions free only parts per billion of a material's rest mass as energy and even nuclear fission and fusion can release only about 1% of it. But when equal quantities of matter and antimatter collide, it's possible for 100% of their combined rest mass to become energy. Since two metric tons is 2000 kilograms and the speed of light is 300,000,000 meters/second, the energy in Einstein's formula is 1.8x1020 kilogram-meters2/second2 or 1.8x1020 joules. To give you an idea of how much energy that is, it could keep a 100-watt light bulb lit for 57 billion years.
While it's true that microwaves twist water molecules back and forth, this twisting alone doesn't make the water molecules hot. To understand why, consider the water molecules in gaseous steam: microwaves twist those water molecules back and forth but they don't get hot. That's because the water molecules beginning twisting back and forth as the microwaves arrive and then stop twisting back and forth as the microwaves leave. In effect, the microwaves are only absorbed temporarily and are reemitted without doing anything permanent to the water molecules. Only by having the water molecules rub against something while they're twisting, as occurs in liquid water, can they be prevented from remitting the microwaves. That way the microwaves are absorbed and never remitted—the microwave energy becomes thermal energy and remains behind in the water.
Visualize a boat riding on a passing wave—the boat begins bobbing up and down as the wave arrives but it stops bobbing as the wave departs. Overall, the boat doesn't absorb any energy from the wave. However, if the boat rubs against a dock as it bobs up and down, it will converts some of the wave's energy into thermal energy and the wave will have permanently transferred some of its energy to the boat and dock.
Yes, VCR's work on the same principle as an audio tape player: as a magnetized tape moves past the playback head, that tape's changing magnetic field produces a fluctuating electric field.

Let’s say that these are the molecules, maybe this is, this one’s the purple one right over here. You have the same two molecules here. Hey, they could get to Free Power more kind of Free Power, they could release energy. But over here, you’re saying, “Well, look, they could. ” The change in enthalpy is negative.
Impulsive gravitational energy absorbed and used by light weight small ball from the heavy ball due to gravitational amplification + standard gravity (Free Power. Free Electricity) ;as output Electricity (converted)= small loss of big ball due to Impulse resistance /back reactance + energy equivalent to go against standard gravity +fictional energy loss + Impulsive energy applied. ” I can’t disclose the whole concept to general public because we want to apply for patent:There are few diagrams relating to my idea, but i fear some one could copy. Please wait, untill I get patent so that we can disclose my engine’s whole concept. Free energy first, i intend to produce products only for domestic use and as Free Power camping accessory.
I might have to play with it and see. Free Power Perhaps you are part of that group of anti-intellectuals who don’t believe the broader established scientific community actually does know its stuff. Ever notice that no one has ever had Free Power paper published on Free Power working magnetic motor in Free Power reputable scientific journal? There are Free Power few patented magnetic motors that curiously have never made it to production. The US patent office no longer approves patents for these devices so scammers, oops I mean inventors have to get go overseas shopping for some patent Free Power silly enough to grant one. I suggest if anyone is trying to build one you make one with Free Power decent bearing system. The wobbly system being shown on these recent videos is rubbish. With decent bearings and no wobble you can take torque readings and you’ll see the static torque is the same clockwise and anticlockwise, therefore proof there is no net imbalance of rotational force.
This simple contradiction dispels your idea. As soon as you contact the object and extract its motion as force which you convert into energy , you have slowed it. The longer you continue the more it slows until it is no longer moving. It’s the very act of extracting the motion, the force, and converting it to energy , that makes it not perpetually in motion.

Generally, when we’re talking of how much energy we’ve got, we don’t look at the whole amount available, since that would produce ridiculous numbers when we count up the number of joules in the various bits of stuff we’re looking at. Instead, what we look at is a local excess of energy over another place and call this what we’ve got. The total energy in a litre of Diesel is massive, but we look at what we get from combustion of it (that converts a very small quantity into KE in the form of heat) and how much more heat we have than the ambient temperature. To convert that heat energy into work we need to let that excess KE move into the ambient and we harness that movement to do the work of moving our car from one place to another. Since we start from stationary and end stationary (and normally end up in the same parking-spot at the end of the day), in fact all that KE we’ve liberated by burning ends up as heat in the atmosphere and we’ve actually done no work at all. Yep, it gets a bit complex when you really follow where all the energy goes to and what has really happened.
I’ll try to restate all this a bit more simply, though. The sum of KE and PE remains constant no matter what you do. We get work done when we harness the movement of energy from one place to another. Energy is conserved, but work is not even though we use the same units to measure it.
A local concentration of kinetic energy will naturally spread out until the energy density is even and without any local high concentrations. This can be seen using water – pour a glass of it into a bowl and you end up with a flat surface where no point is higher than another. Pour the glass of water through a turbine and you can get work done in the process, but you don’t have to do this so the work obtained can be anywhere from zero to (almost) the available excess energy when the glassful gets poured.
Part of Quantum Theory says that there is a residual amount of kinetic energy left even at absolute zero, and that things will thus still move. Some people think therefore that this Zero-Point Energy (ZPE) should be able to be tapped.

Since most light sources put more energy in the red portion of the spectrum than in the blue portion of the spectrum, the blue cloth absorbs more energy than the red cloth. So the sequence of temperatures you observed is the one you should expect to observe.
One final note: most light sources also emit invisible infrared light, which also carries energy. Most of the light from an incandescent lamp is infrared. You can't tell by looking at a piece of cloth how much infrared light it absorbs and how much it reflects. Nonetheless, infrared light affects the cloth's temperature. A piece of white cloth that absorbs infrared light may become surprisingly hot and a piece of black cloth that reflects infrared light may not become as hot as you would expect.
A roller coaster is a gravity-powered train. Since it has no engine or other means of propulsion, it relies on energy stored in the force of gravity to make it move. This energy, known as "gravitational potential energy," exists because separating the roller coaster from the earth requires work—they have to be pulled apart to separate them. Since energy is a conserved quantity, meaning that it can't be created or destroyed, energy invested in the roller coaster by pulling it away from the earth doesn't disappear. It becomes stored energy: gravitational potential energy. The higher the roller coaster is above the earth's surface, the more gravitational potential energy it has.
Since the top of the first hill is the highest point on the track, it's also the point at which the roller coaster's gravitational potential energy is greatest. Moreover, as the roller coaster passes over the top of the first hill, its total energy is greatest. Most of that total energy is gravitational potential energy but a small amount is kinetic energy, the energy of motion.
From that point on, the roller coaster does two things with its energy. First, it begins to transform that energy from one form to another—from gravitational potential energy to kinetic energy and from kinetic energy to gravitational potential energy, back and forth. Second, it begins to transfer some of its energy to its environment, mostly in the form of heat and sound. Each time the roller coaster goes downhill, its gravitational potential energy decreases and its kinetic energy increases. Each time the roller coaster goes uphill, its kinetic energy decreases and its gravitational potential energy increases. But each transfer of energy isn't complete because some of the energy is lost to heat and sound.

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the act, process, or state of changing place or position; movement; the passing of a body from one place or position to another, whether voluntary or involuntary; -- opposed to rest
power of, or capacity for, motion
direction of movement; course; tendency; as, the motion of the planets is from west to east
change in the relative position of the parts of anything; action of a machine with respect to the relative movement of its parts
movement of the mind, desires, or passions; mental act, or impulse to any action; internal activity
a proposal or suggestion looking to action or progress; esp., a formal proposal made in a deliberative assembly; as, a motion to adjourn
an application made to a court or judge orally in open court. Its object is to obtain an order or rule directing some act to be done in favor of the applicant
change of pitch in successive sounds, whether in the same part or in groups of parts
a puppet show or puppet
to make a significant movement or gesture, as with the hand; as, to motion to one to take a seat
to make proposal; to offer plans
to direct or invite by a motion, as of the hand or head; as, to motion one to a seat
to propose; to move
In physics, motion is a change in position of an object with respect to time and its reference point. Motion is typically described in terms of displacement, velocity, acceleration, and time. Motion is observed by attaching a frame of reference to a body and measuring its change in position relative to another reference frame. A body which does not move is said to be at rest, motionless, immobile, stationary, or to have constant position. An object's motion cannot change unless it is acted upon by a force, as described by Newton's first law. An object's momentum is directly related to the object's mass and velocity, and the total momentum of all objects in a closed system does not change with time, as described by the law of conservation of momentum. As there is no absolute frame of reference, absolute motion cannot be determined. Thus, everything in the universe can be considered to be moving. More generally, the term motion signifies a continuous change in the configuration of a physical system. For example, one can talk about motion of a wave or a quantum particle where the configuration consists of probabilities of occupying specific positions.
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