Compressed air escaping from a punctured football___________________?
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Answer: B. becomes cooler1
Explanation
Rapid expansion of escaping air drops the gas pressure and temperature quickly. Work is done by the expanding gas against the surrounding atmospheric pressure. This rapid adiabatic process converts thermal energy into mechanical expansion work. Throttling and rapid expansion processes typically cause significant fluid temperature drops. Compressed air stores potential energy that is released rapidly during punctures. The Joule Thomson effect explains how real gases cool upon expansion.
This principle explains why aerosol spray cans feel cold during prolonged usage. Air conditioning systems utilize expansion valves to produce necessary cooling effects. Punctured tires or footballs demonstrate natural thermodynamic cooling in everyday life. Option A contradicts thermodynamics because expansion without heating causes cooling. Option C ignores the conversion of internal thermal energy into expansion work. Option D incorrectly suggests ambient humidity dictates the core thermodynamic expansion behavior.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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