How does the acoustic velocity in an ideal gas vary relative to its thermodynamic state__________________?
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Answer: E. absolute temperature
Explanation
The acoustic velocity in an ideal gas is directly proportional to the square root of temperature. Thermodynamic absolute temperature determines the average translational kinetic energy of gas molecules directly. Faster moving molecules transmit pressure disturbances more rapidly through the gaseous medium. Acoustic velocity represents the speed at which small amplitude pressure waves propagate through a fluid. For an ideal gas, speed of sound equals the square root of the product of specific heat ratio, gas constant, and temperature. Absolute temperature is measured in Kelvin, establishing a direct baseline for thermal energy calculations.
Aerodynamicists account for ambient temperature changes when calculating Mach numbers for aircraft flight testing. Gas turbine engine performance depends heavily on local acoustic velocities within compressor and turbine stages. Meteorologists use temperature profiles to understand how sound waves refract through the Earth atmosphere. Option A is incorrect because pressure changes alone do not alter ideal gas sound speed at constant temperature. Option C is incorrect because density variations are already coupled directly to pressure and temperature states. Option D refers to a general elasticity concept rather than the specific thermal variable governing gases.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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