Energy Stores and Systems.

Energy is never used up. Instead it's just transferred between different energy stores and different objects...

Energy is Transferred between Stores.

When energy is transferred to an object, the energy is stored in one of the object's energy stores.

The 10 energy stores are:

1) Thermal

2) Kinetic

3) Gravitational potential

4) Elastic potential

5) Chemical

6) Magnetic

7) Electrostatic

8) Nuclear

9) Light

10) Sound

Energy is transferred mechanically (by a force doing work), electrically (work done by moving charges), by heating or by radiation (e.g. light, or sound).

When a System Changes, Energy is Transferred.

1) A system means a single object (e.g. the air in a piston) or a group of objects (e.g. 2 colliding vehicles) that you're interested in.

2) When a system changes, energy is transferred. It can be transferred into or away from the system, between different objects in the system or between different types of energy stores.

3) Closed systems are systems where neither matter nor energy can enter or leave. The net change in the total energy of a closed system is always zero.

…