Temperature measurement relies upon_________________?
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Answer: B. zeroth law of thermodynamics
Explanation
Zeroth law of thermodynamics establishes that thermal equilibrium is transitive among bodies. This principle allows a calibrated thermometer to indicate the temperature of any system in thermal equilibrium with it. Therefore, the logical foundation for all temperature measurement relies directly on the zeroth law. Ralph Fowler formulated the zeroth law after the first and second laws were already established. Thermal equilibrium means no net heat flows between two bodies when they are placed in thermal contact. Temperature scales like Celsius and Kelvin are calibrated using fixed reference points like freezing and boiling water.
Thermocouples, resistance thermometers, and glass thermometers all operate based on zeroth law equilibrium principles. Industrial process control systems require frequent sensor calibration ensuring compliance with thermal equilibrium standards. Thermodynamic property measurements depend on accurate temperature readings for accurate cycle analysis. Thermodynamic properties describe system characteristics but do not provide the foundational law for measuring temperature. First law of thermodynamics governs energy conservation and heat-work conversions rather than temperature measurement. Second law establishes entropy direction and heat engine efficiency limits, not thermal equilibrium measurement.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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