An inventor claims a heat engine produces 20 h.p. while receiving 400 kcal/min of heat between 227°C and 27°C. How should this claim be evaluated__________________?
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Answer: B. not possible
Explanation
Evaluating the proposed heat engine against the Carnot limit proves the claim violates thermodynamics. Calculating maximum theoretical efficiency reveals the inventor's claim exceeds physical laws. Energy conservation and entropy principles confirm that such high output is impossible. The second law of thermodynamics limits heat engine efficiency based on reservoir temperatures. Carnot efficiency depends entirely on absolute hot and cold temperature extremes. Perpetual motion claims of the second kind are consistently disproven by thermodynamic analysis.
Patent offices routinely reject engine designs claiming efficiencies exceeding thermodynamic limits. Power plant engineers use Carnot limits to evaluate real-world thermodynamic cycle performance. Understanding thermodynamic laws prevents wasting resources on impossible engineering projects. Option A is incorrect because violating thermodynamic laws makes the claim impossible. Option C wrongly implies that sophisticated engineering can overcome fundamental physical laws. Option E is false since theoretical physics explicitly prohibits this engine performance.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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