Kelvin-Planck’s law governs___________________?
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Answer: C. conversion of heat into work
Explanation
The Kelvin-Planck statement restricts heat engines from converting all absorbed heat into work. It dictates that some thermal energy must be rejected to a low-temperature sink. This principle governs the limitations of converting thermal energy into mechanical work. The second law of thermodynamics is expressed through Kelvin-Planck and Clausius statements. Heat engines require a temperature differential to continuously convert heat into useful work. Perpetual motion machines of the second kind are prohibited by the Kelvin-Planck law.
Thermal power plant design must incorporate condensers to reject waste heat to ambient sinks. Engineers analyze second law constraints to maximize the practical work output of thermal cycles. Understanding heat-to-work conversion limits prevents unrealistic performance expectations in design. Option A incorrectly suggests conservation of heat, which violates thermodynamic principles. Option B relates to work conservation rather than heat-to-work conversion limitations. Option E refers to mass conservation principles governed by continuity equations.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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