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A Carnot heat engine absorbs 3 × 10⁶ cal of heat from a source maintained at 627°C and rejects heat to a sink at 27°C. The work output of the engine is

1. 4.2 × 10⁶ J
2. 8.4 × 10⁶ J
3. 16.8 × 10⁶ J
4. zero

Correct answer: 8.4 × 10⁶ J

Solution

The work output of a Carnot engine can be calculated using the efficiency formula, which is based on the temperatures of the heat source and sink. Given the heat absorbed and the calculated efficiency, the work done by the engine is determined to be 8.4 × 10⁶ J, making this the correct option.

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