AQA P1 Conservation and dissipation of energy

Kinetic Energy

the energy that an object possesses due to its motion

Elastic Energy

the energy stored by an object when it is squashed or stretched

Gravitational Energy

the energy an object has due to its position above Earth

Chemical energy

energy stored in the bonds of chemical compounds

Thermal energy

The energy stored in a system due to its temperature.

Renewable

A resource which is generated from sources which will not run out.

Reliable

A resource that can be used continuously whatever the weather conditions.

Energy

The ability to do work. Measured in Joules (J).

Power

The rate of transfer of energy. Measured in Watts (W).

Equation that relates energy, power and time

P = E/t.

Fossil fuels

Non-renewable energy resources formed from the remains of ancient plants or animals. Examples are coal, crude oil and natural gas.

conservation of energy

energy cannot be created or destroyed

dissipated energy / dissipation of energy

the energy that is not usefully transferred and stored in less useful ways

efficiency

useful energy transferred by a device ÷ total energy supplied to the device

elastic potential energy

energy stored in an elastic object as a result of it being deformed. For example, a stretched spring

Hooke's Law

the extension of a spring is directly proportional to the force applied, as long as its limit of proportionality is not exceeded

input energy

energy supplied to a device

spring constant

force per unit extension of a spring

useful energy

energy transferred to where it is wanted in the way that is wanted

wasted energy

energy that is not usefully transferred

work

the energy transferred by a force.

Work done

Work done (joules, J) = force (newtons, N) x distance moved in the direction of the force (metres, m)