Physicsmedium · Past Paper
Calculate the energy used by a 50W fan in 20 hours.
A1 kWh
B10 kWh
C1000 J
D0.5 kWh
✓ Correct Answer: A — 1 kWh
Energy = Power * Time = 50W * 20h = 1000 Wh = 1 kWh.
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