GCSE Physics: Energy — Topic Revision Workbook

Inside GCSE Physics: Energy — Topic Revision Workbook

name energy stores and describe transfers, calculate kinetic energy Ek = ½mv², gravitational PE = mgh and elastic PE = ½ke², work through specific heat capacity E = mcΔθ and power P = E/t, then master conservation, dissipation, efficiency and renewable and non-renewable energy resources. About 30 minutes.

Learning objectives

• energy stores and transfers — kinetic, gravitational potential, elastic potential, thermal, chemical and nuclear stores, and transfers by heating, waves, electrically and mechanically;
• energy calculations — kinetic energy Ek = ½mv², gravitational PE = mgh (g = 9.8 N/kg) and elastic PE = ½ke²;
• heating and power — specific heat capacity E = mcΔθ and power P = E/t in watts;
• conservation and efficiency — energy conservation, dissipation, efficiency = useful ÷ total × 100%, and reducing unwanted transfers by insulation and lubrication;
• energy resources — renewable resources (wind, solar, hydro) and non-renewable fossil fuels (coal, oil, gas), and a full exam-style 6-mark question.

Activities in this book

1. Task 1 — Energy Stores & Transfers

   energy is never made or destroyed — it is stored and transferred. Learn the key stores: kinetic (movement), gravitational potential (height), elastic potential (stretch), thermal (hot objects), chemical (fuels, food, batteries) and nuclear. Energy is transferred by heating, by waves, electrically or mechanically (by a force doing work).

2. Task 2 — Kinetic, Gravitational & Elastic Energy

   learn the three equations. Kinetic energy Ek = ½mv² (remember to square the speed before halving). Gravitational potential energy = mgh, with g = 9.8 N/kg. Elastic potential energy = ½ke², where k is the spring constant and e is the extension. Always show your working and give the unit joules (J).

3. Task 3 — Specific Heat Capacity & Power

   to heat something up, use E = mcΔθ: energy = mass × specific heat capacity × temperature change. Water has a high c of 4200 J/kg°C, so it takes a lot of energy to warm. Power is the rate of transferring energy: P = E/t, measured in watts (W), where 1 watt = 1 joule per second.

4. Task 4 — Conservation, Efficiency & Resources

   energy is always conserved, but some is dissipated (wasted) to the surroundings, usually as heat. Efficiency = useful output ÷ total input (× 100%). We reduce unwanted transfers with insulation (traps heat) and lubrication (cuts friction). Energy resources are either renewable (wind, solar, hydro) or non-renewable (coal, oil, gas — the fossil fuels).

5. Task 5 — Exam-Style 6-Marker

   a 6-mark question rewards clear, linked physics. Plan first: name the energy stores at the start and end, describe the transfer, and use the idea that energy is conserved but some is dissipated. Where you can, name an equation or give a number. Write in full sentences and use the correct key terms.

Suggestions for teaching

• Stores first, then transfers. Make sure learners can name every energy store before describing how energy moves between them — it underpins every calculation.
• Drill the three energy equations. Practise Ek = ½mv² (square the speed first), GPE = mgh with g = 9.8, and elastic PE = ½ke² until they are automatic.
• Keep units tidy. Energy in joules, power in watts, and always convert cm to m before using extensions or heights.
• Model efficiency. Show useful ÷ total × 100%, and stress that the “lost” energy is dissipated, not destroyed.
• Practise the 6-marker. Teach learners to plan marking points (stores, transfer, dissipation) before writing full sentences.