A 60 W lamp stays on for 5 hours. How much energy does it use?
Answer and explanation
Correct answer: A. 0.3 kWh
- Step 1: Convert 60 W to 0.06 kW. Step 2. Energy = 0.06 kW x 5 h = 0.3 kWh. Answer: 0.3 kWh. Why not the others: The wrong values mis-convert watts to kilowatts.
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