Energy units: Convert watt-hour to joules. One watt-hour represents the energy expended by 1 watt sustained for 1 hour. What is this energy in joules? Choose the correct option.

Q: Energy units: Convert watt-hour to joules. One watt-hour represents the energy expended by 1 watt sustained for 1 hour. What is this energy in joules? Choose the correct option.

Given 1 W = 1 J·s⁻¹ 1 hour = 3600 s Calculation Energy = Power × Time = 1 J·s⁻¹ × 3600 s = 3600 J. Check 1 kWh = 1000 W × 3600 s = 3.6 × 106 J (so 1 Wh = 3.6 × 103 J). Final Answer 3600 J

Difficulty: Easy

3600 J
360 J
36,000 J
3.6 × 10⁶ J

Correct Answer: 3600 J

Explanation:

Given

1 W = 1 J·s⁻¹
1 hour = 3600 s

Calculation
Energy = Power × Time = 1 J·s⁻¹ × 3600 s = 3600 J.

Check
1 kWh = 1000 W × 3600 s = 3.6 × 10⁶ J (so 1 Wh = 3.6 × 10³ J).

Final Answer
3600 J

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