- Power
- The rate of energy transfer or the rate of doing work. Measured in watts (W).
- Watt (W)
- The SI unit of power. 1 W = 1 joule per second (1 J/s).
- Kilowatt (kW)
- A unit of power equal to 1,000 watts. Used for most household appliances.
- Kilowatt-hour (kWh)
- A unit of energy equal to 3,600,000 J. Used by energy companies to measure electricity consumption. 1 kWh = 1 kW × 1 hour.
- Work done
- The energy transferred when a force moves an object through a distance. Measured in joules (J).
This definitions covers Key Definitions within Power for GCSE Physics. Revise Power in Energy for GCSE Physics with 14 exam-style questions and 25 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 5 of 12 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Practice questions for Power
Which of the following is the correct definition of power?
A microwave oven transfers 54,000 J of energy. It has a power rating of 900 W. Calculate how long the microwave was switched on. Use the equation: power = energy transferred / time Give your answer in seconds (s).
Quick recall flashcards
What is power?
Power is the rate at which energy is transferred or work is done. It is measured in watts (W).
What is mechanical power?
Mechanical power is the rate at which mechanical work is done or mechanical energy is transferred, calculated using P = W/t.