A Carnot engine operates between 400 K and 300 K. If it absorbs 800 J from the hot reservoir per cycle, the work output per cycle is:
A100 J
B200 J
C400 J
D600 J
Answer & Solution
Correct answer: B. 200 J
1. η = 1 − T₂/T₁ = 1 − 300/400 = 0.25 (25 %).
2. W = η × Q₁ = 0.25 × 800 = 200 J.
3. Heat rejected Q₂ = Q₁ − W = 600 J (a useful cross-check).
_Source: NCERT Class 11 Physics Ch 11, §11.10 Carnot Engine_
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