What condition must be met for a thermodynamic cycle to be reversible________________?
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Answer: D. all of the above
Explanation
Reversible thermodynamic cycles must completely eliminate all sources of mechanical and fluid friction losses. Heat transfer must occur across infinitely small temperature differences between the working fluid and external sources. Unresisted expansions cause entropy generation, so reversible processes require smooth, externally balanced expansion stages. Reversibility is an idealized theoretical concept where a system can return to its initial state without leaving changes. The second law of thermodynamics establishes that real processes are inherently irreversible due to friction and turbulence. Carnot cycles represent the ultimate standard of reversible performance operating between two constant temperature reservoirs.
Focusing only on avoiding free expansion ignores critical temperature matching requirements during external heat exchange. Matching source temperatures alone fails to guarantee reversibility if unresisted fluid expansion or friction occurs inside. Selecting individual conditions instead of all combined criteria would still result in irreversible thermodynamic cycles.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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