The principle that energy cannot be created or destroyed, only transformed from one modality to another, is derived from_________________?
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Answer: B. first law of thermodynamics
Explanation
The first law of thermodynamics formally establishes the principle of energy conservation. It states that energy cannot be created nor destroyed, only converted between different forms. This foundational physical law governs all thermal and mechanical energy transfer calculations. Energy conservation applies universally across physics, chemistry, and engineering disciplines. Thermodynamic systems track energy crossing boundaries as heat and work interactions. Perpetual motion machines of the first kind are impossible because they violate this law.
Power generation plants operate by converting chemical energy into thermal and mechanical work. Energy audits use first law principles to track efficiency losses in industrial manufacturing. Designing sustainable energy systems requires strict adherence to energy conservation laws. Option A refers to the zeroth law governing thermal equilibrium and temperature measurement. Option C refers to the second law governing entropy and direction of energy transfer. Option E cites the Clausius statement which is a specific expression of the second law.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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