__________________ of air does not rise with increasing temperature?
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Answer: A. Density
Explanation
Air expands when heated, causing its mass per unit volume to decrease significantly. Thermal diffusivity increases with temperature due to changes in thermal conductivity and specific heat. Viscosity and thermal conductivity of gases both increase as temperature rises due to molecular activity. Density is defined as mass divided by volume for any given substance. Thermal expansion causes most fluids to occupy greater volumes at elevated temperatures. Kinetic theory explains how molecular collisions increase transport properties at higher temperatures.
Atmospheric convection currents form because warm air decreases in density and rises upward. Heat exchanger designs account for temperature-dependent fluid properties to maintain efficiency. Ventilation systems rely on temperature differences to drive natural airflow patterns. Thermal diffusivity rises with temperature because molecular thermal velocity increases accordingly. Viscosity of gases increases with temperature due to enhanced momentum transfer between molecules. Thermal conductivity grows larger as higher temperatures accelerate molecular energy transfer rates.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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