Power (AQA GCSE Physics Combined Science): Revision Notes

1.1.10 Power

Power

Formula

infoNote

Formula

$$\text{Power} = \frac{\text{energy transferred}}{\text{time}} = \frac{\text{work done}}{\text{time}} = P = \frac{E}{t} = \frac{W}{t}$$

Variables

• $P$: Power, in watts (W)
• $E$: Energy transferred, in joules (J)
• $t$: Time, in seconds (s)
• $W:$ Work done, in joules (J)

Explanation

• Power (P): Measured in watts (W), represents the rate of energy transfer or work done.
• Energy Transfer: 1 joule per second equals a power of 1 watt.
• Comparing Motors: If two motors, A and B, perform the same work, the motor that completes the work faster is more powerful because the energy is transferred at a faster rate.