What principle is established by the first law of thermodynamics_______________________?
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Answer: C. heat and work are mutually convertible
Explanation
The first law of thermodynamics is a statement of the conservation of energy principle. It proves that heat and work are mutually convertible forms of thermal energy transfer. Energy cannot be created or destroyed, only converted between heat and mechanical work. James Prescott Joule experimentally demonstrated the mechanical equivalent of heat. 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 plant engineers use the first law to perform energy balance audits on turbines. Internal combustion engines convert fuel heat energy into useful mechanical work output. HVAC system design relies on energy conservation principles to calculate heating loads. Mass-energy equivalence is governed by Einstein's theory of relativity rather than thermodynamics. Carnot efficiency deals with the second law of thermodynamics regarding temperature limits. Heat flow direction from hot to cold substances is established by the second law.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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