Energy: GCSE Physics
Energy stores and transfers, conservation and dissipation, KE GPE EPE equations, power, efficiency, insulation and energy resources
The short version
Name stores and pathways, use KE = ½mv², GPE = mgh and EPE = ½ke², calculate power and efficiency, and compare energy resources.
Key idea
Then pick one of four pathways: mechanically · electrically · by heating · by radiation
Grade 2–3: Energy moves from one store to another. A falling apple had energy because it was high up, then it was moving.
Grade 5–6: I write chemical store of the battery to kinetic store of the motor, transferred electrically. Work done is energy transferred: W = Fs.
Grade 9: A closed system has no energy in or out, so the total is constant even though stores swap. I never write energy is used up. A kettle is electrical pathway into the thermal store of the element, then heating into the thermal store of the water.
Go a bit deeper
A system is the object or group of objects you are looking at. Lifting a box does mechanical work and increases its gravitational potential store. Anything moving has energy in its kinetic store.
Worked example
Worked example
Grade 2–3: Energy moves from one store to another. A falling apple had energy because it was high up, then it was moving. Grade 5–6: I write chemical store of the battery to kinetic store of the motor, transferred electrically. Work done is energy transferred: W = Fs. Grade 9: A closed system has no energy in or out, so the total is constant even though stores swap. I never write energy is used up. A kettle is electrical pathway into the thermal store of the element, then heating into the thermal store of the water.
Lessons in this topic
- Energy stores and transfers
- Conservation and dissipation
- KE GPE EPE equations
- Power efficiency
- Insulation and conduction
- Energy resources
In the app each lesson is video (when we have a real YouTube id) then intro, learn and summary steps.
What the examiner wants
Write store-to-store transfers, show working with units, and explain dissipation to the thermal store of the surroundings. Efficiency = useful ÷ total.
Try these questions
Cover the answers and have a go first. Worked solutions are underneath.
Which of these is an energy store?
A ball falls. Which transfer is correct (ignore air resistance)?
Work done by a 40 N force moving an object 3.0 m in the direction of the force is
Energy in a closed system is
Common mistakes
- Do not write "the energy is used up". Energy is transferred. "Used up" scores zero on a store question.
- Do not say energy is "lost". Say it is dissipated or transferred to a thermal store.
- A common dump is (1/2 x m x v)^2. Square the speed only. Do not square k. Do not use the full length of the spring as e.
- Efficiency cannot be greater than 1 (or 100%). If the calculator says 250%, you swapped useful and total. Do not leave time in minutes inside P = E/t if you want watts from joules.
Answers and working
Frequently asked questions
Is GCSE Energy on Combined Science and Triple?
Energy is on Combined Science and on Triple Physics. Progress is shared in the ReviseEasy app.
Which exam board is this Energy page for?
The ideas are board-agnostic for AQA, Edexcel, OCR, WJEC and CCEA. Paper lengths and question numbers differ — check your specification.
Is Energy Foundation or Higher?
The core ideas appear on both tiers. Higher papers add extra application and some HT-only detail, marked in lessons with a Higher badge.
Learn, try, get feedback, fix the mistake
Open the stepped lesson, then the quiz with hints. Required-practical and calculation questions use the same method you will need in the paper.
Learn Energy on ReviseEasy →Related revision
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