Physics A-Level
Efficiency
What Efficiency means in Physics A-Level, as defined for AQA, OCR.
Definitions of Efficiency
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Reference: OCR
The ratio of useful output energy to total input energy, expressed as a percentage using efficiency = (useful output energy / total input energy) × 100%.
The ratio of useful output to total input, recognising that friction causes energy dissipation as thermal energy.
Output power divided by input power, often expressed as a percentage.
Topics that use Efficiency
- The operation of a transformer (A-level only) (AQA A-Level)
- Work and power (A-level only) (AQA A-Level)
- Power (OCR A-Level)
Related terms
- Force and motion
- Frictional torque
- Hysteresis
- Mechanical power
- Power
- Quantitative analysis of power loss
- SI units and conversions
- Unit conversion of time
Using Efficiency in the exam
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