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KCET2020PhysicsThermodynamics

In an adiabatic expansion of an ideal gas the product of pressure and volume

Options

  1. Adecreases
  2. Bincreases
  3. Cremains constant
  4. Dat first increases and then decreases

Correct answer

A. decreases

Step-by-step solution

In an adiabatic expansion, internal energy decreases and hence temperature also decreases. Hence, from ideal gas equation, p V=n R T Since, T decreases. Hence, p V also decreases.

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