Energy Stores & Transfers - AQA GCSE Physics Revision

Topic overview

What you need to know

Energy Stores & Transfers is a key part of GCSE Physics. Choose the right model or equation, track units carefully and connect calculations to physical meaning. The energy stored in a moving object. KE = ½mv² (m = mass in kg, v = speed in m/s). The energy stored in an object due to its height above the ground. GPE = mgh (m = mass, g = 9.8 m/s², h = height). The energy stored in a stretched or compressed object. EPE = ½ke² (k = spring constant, e = extension).

Exam tip

Write the equation, substitute with units, calculate, then round only at the end.

Revision notes

Core ideas

Secure these ideas first. Say each definition in your own words, then connect it to the topic overview.

Kinetic Energy: The energy stored in a moving object. KE = ½mv² (m = mass in kg, v = speed in m/s).
Gravitational Potential Energy: The energy stored in an object due to its height above the ground. GPE = mgh (m = mass, g = 9.8 m/s², h = height).
Elastic Potential Energy: The energy stored in a stretched or compressed object. EPE = ½ke² (k = spring constant, e = extension).
Conservation of Energy: Energy cannot be created or destroyed, only transferred from one store to another.

Revision notes

Apply it in the exam

The exam will rarely ask for an isolated definition. Practise selecting the right idea and using it as part of a complete explanation or method.

Efficiency: Efficiency = (useful energy output ÷ total energy input) × 100%. Always less than 100% due to waste energy.
Power: The rate of energy transfer. Power = energy transferred ÷ time. Measured in watts (W). 1W = 1 J/s.
Specific Heat Capacity: The energy needed to raise the temperature of 1 kg of a substance by 1°C. E = mcΔθ.
Dissipated Energy: Energy that is 'wasted' and spread out to the surroundings, usually as heat, making it less useful.

Core knowledge

Key facts for Energy Stores & Transfers

8 essentials

Kinetic Energy

The energy stored in a moving object. KE = ½mv² (m = mass in kg, v = speed in m/s).

Gravitational Potential Energy

The energy stored in an object due to its height above the ground. GPE = mgh (m = mass, g = 9.8 m/s², h = height).

Elastic Potential Energy

The energy stored in a stretched or compressed object. EPE = ½ke² (k = spring constant, e = extension).

Conservation of Energy

Energy cannot be created or destroyed, only transferred from one store to another.

Efficiency

Efficiency = (useful energy output ÷ total energy input) × 100%. Always less than 100% due to waste energy.

Power

The rate of energy transfer. Power = energy transferred ÷ time. Measured in watts (W). 1W = 1 J/s.

Specific Heat Capacity

The energy needed to raise the temperature of 1 kg of a substance by 1°C. E = mcΔθ.

Dissipated Energy

Energy that is 'wasted' and spread out to the surroundings, usually as heat, making it less useful.

Active recall

Close the notes and answer these

1.Without looking, explain kinetic energy and give one example or consequence.
2.Without looking, explain gravitational potential energy and give one example or consequence.
3.Without looking, explain elastic potential energy and give one example or consequence.
4.Without looking, explain conservation of energy and give one example or consequence.

Content reviewed 23 July 2026 against the current linked specification.

Finished learning?

Mark the notes complete, then test what you can recall.

Official AQA specification

Next topicElectricity