Physics
Grade-9
Easy
Question
A load uses 2 W of power in 10 s. The work done by the power supply is approximately
- 20 J
- 150 J
- 37.5 J
- 2/75 J
Hint:
Power is rate of doing work.
The correct answer is: 20 J
- Work done can be calculated by multiplying the power into time.
- Hence 2W * 10 seconds = 20J.
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