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The reversible expansion of an ideal gas under adiabatic and isothermal conditions is shown in the figure. Which of the following statements is incorrect?

Options

  1. AT 3 > T 1
  2. BT 1 = T 2
  3. CΔ U isothermal > Δ U adiabatic
  4. DW isothermal > w adiabatic

Correct answer

A. T 3 > T 1

Step-by-step solution

In an isothermal process, temperature is constant T 2 = T 1 Area under P - V graph is more is isothermal W isothermal > w adiabatic Now Δ U isothermal = 0 In adiabatic T 1 V 1 γ - 1 = T 3 V 3 γ - 1 T 3 T 1 = V 1 V 3 γ - 1 T 3 < T 1 Hence internal energy decreases Δ U isothermal > Δ U adiabatic

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