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Thermodynamics

Question
CBSEENPH11026381

The volume of an ideal gas is doubled in an isothermal process. Then, which of the following is true?

  • Work done by the gas is positive

  • Work done by the gas is negative

  • Internal energy of the system decreases

  • Internal energy of the system increases

Solution

A.

Work done by the gas is positive

For isothermal process

   dU = 0

Work done = dW

                 = ρ ( v2 - v1 )

∴  dW = + pV                          [ V2 = 2V1 = 2V ]