The conservation of energy
The capacity for doing work. can be When something is moved from one place to another. This may be people, objects or energy. usefully, stored or The spreading out and transfer of energy stores into less useful forms, such as thermal energy causing the surroundings to heat up. Dissipated energy is often referred to as 'wasted' energy, since it is not transferred to a useful output. , but it cannot be created or destroyed.
In all cases, energy comes from one store and is transferred to another store. This means that all the energy in the Universe was present at the The scientific theory that describes the early development of the Universe. and will still be around at the very end of time.
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Examples of conservation of energy
The skydiver
When a skydiver jumps out of a plane, he begins to lose The energy stored by an object lifted up against the force of gravity. Also known as GPE. as his height decreases and he gains Energy which an object possesses by being in motion. as his speed increases.
However, not all of the gravitational potential energy is transferred into kinetic energy as some work is done pushing against the air particles. Some of the gravitational potential energy is transferred to the air particles and is stored as The total kinetic energy and potential energy of the particles in an object..
Smartphones
All smartphones contain a battery that stores chemical energy. When a smartphone is in use, electrical work is done and a current flows - the battery鈥檚 chemical energy is transferred in a number of ways to light the screen and produce sound.
The light that comes from a smartphone is emitted as light radiation, and the sound waves are produced by a speaker that vibrates back and forth.
In addition to this, many smartphones also heat up when used, so A type of stored energy. It is taken in when chemical bonds break, and given out when chemical bonds are made. is also transferred into internal energy. This energy is stored in the atoms of the smartphone鈥檚 A material which allows charge to move easily through it. and it is these atoms that emit infrared Energy transferred as a wave聽spreading out from a source聽- eg light, infrared, sound..