Physics - Paper 1

Energy

Energy stores

• Energy can be stores in a system in lots of different ways. Some stores of energy are:

Kinetic store

- The energy stored by an object’s movement.

Gravitational

The energy stored in objects raised above the Earth’s surface. This energy exists because of the Earth’s gravitational field.

Chemical store

The energy stored by the chemical bonds between atoms.

An example of storing this energy is adding it to your body’s chemical store when you eat food. The energy is stores there until you need it. Your body then transfers it to your kinetic store to move about.

Elastic potential store

The energy stored when an object is being stretched, compressed or squashed.

Nuclear store

The energy stores in the nucleus of an atom. The energy in the nuclear store can be released by radioactive decay.

Internal(thermal) store

The internal store of energy is the sum of the kinetic energy store in the particles bonds between particles object.

Internal energy

It is the amount of energy in an object’s internal energy is the sum(total) of the kinetic energy and potential energy stored in the object’s particles.

+ Temperature

• The temperature of a body (Object) is a measure of the energy in the kinetic stores of its particles.

• Increasing a body’s temperature increases the energy in the kinetic stores of the body’s particles, which means that the energy in the body’s internal store also increases.

Kinetic energy storage

Kinetic energy stored equation

The kinetic energy (in J) = ½ x m x v²

Gravitational potential energy stored equation

Change in gravitational potential energy = mass x gravitational field strength x change in height