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For a gas undergoing an adiabatic change, its pressure varies as the cube of its absolute temperature. The value of the ratio Cₚ/C_v for this gas is

1. 4/3
2. 2
3. 5/3
4. 3/2

Correct answer: 3/2

Solution

In an adiabatic process, the relationship between pressure and temperature for an ideal gas can be expressed using the specific heat ratio, which is defined as Cₚ/C_v. For this gas, the given relationship indicates that the specific heat ratio is 3/2, consistent with the behavior of a monatomic ideal gas.

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