Efficiency Calculations - AQA GCSE Physics Practice Book

Efficiency questions come in two forms (decimal and percentage) and use two different versions of the formula (energy and power), which means students need to be comfortable switching between all four combinations. This AQA GCSE Physics workbook covers them all with 12 scaffolded questions using the EVERY method framework.

The EVERY method breaks each calculation into clear steps: Equation, Values, Enter values into the equation, Rearrange if needed, Your units. Every question has a structured EVERY table for students to complete, building a consistent problem-solving habit. Questions get progressively harder: Q1-3 are straightforward, Q4-6 introduce unit conversions, and Q7-12 require rearranging the formula.

What’s inside:

• 12 progressive questions on Efficiency (efficiency = useful output / total input, using energy or power)
• Structured EVERY method table on every question page
• Progressive difficulty: simple substitution, then unit conversions, then rearranging
• Self-assessment tracker with “What made me stuck?” reflection checklist
• Full worked answers for all 12 questions using the EVERY method steps

AQA specification reference: 6.1 Energy (Combined Science and Triple Physics)

Efficiency calculations require students to identify the useful energy output (or useful power output) and the total energy input (or total power input), then divide. Some questions ask for a decimal, others ask for a percentage. Real-world contexts include light bulbs, motors, and power stations.

Common student mistakes this workbook addresses: putting input on top instead of output, giving efficiency greater than 1 (or greater than 100%) without questioning it, not converting between decimal and percentage forms, and confusing wasted energy with useful energy.

Suitable for AQA GCSE Combined Science and Physics (Triple). Works for both foundation and higher tier students.