During an isothermal process, internal energy________________?
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Answer: C. remains constant
Explanation
An isothermal process is defined by a completely constant temperature throughout the entire thermodynamic procedure. Internal energy of an ideal gas depends exclusively on its absolute temperature according to Joule's law. Since temperature remains unchanged during an isothermal expansion or compression, the internal energy also stays constant. Thermodynamic systems undergoing isothermal changes typically require very slow heat transfer with a constant temperature reservoir. The internal energy change for an ideal gas is calculated by multiplying mass, specific heat, and temperature difference. Boyle's law accurately describes the pressure and volume relationship for an isothermal ideal gas process.
Internal energy cannot increase during an isothermal process because doing so would violate the constant temperature rule. Decreasing internal energy would require a drop in temperature, which contradicts the definition of an isothermal process. Fluctuating internal energy profiles occur during polytropic or adiabatic processes rather than true isothermal ones.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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