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JEE Main 2024 (29 Jan, Shift 1) · P-V Diagrams & Cyclic Processes

P-V Diagrams & Cyclic Processes question from JEE Main 2024 (29 Jan, Shift 1)

Q31JEE Main 2024 · 29 JAN · SHIFT 1Medium

P-V Diagrams & Cyclic Processes

A thermodynamic system is taken from an original state AA to an intermediate state BB by a linear process as shown in the figure. Its volume is then reduced to the original value from BB to CC by an isobaric process. The total work done by the gas from AA to BB and BB to CC would be:

Figure

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Answer: (a)

  1. A→B→C→A is a closed triangle traversed clockwise, so W=W = enclosed area (positive).
  2. Area =12×(7−3) m3×(8000−4000) dyne/cm2= \frac{1}{2} \times (7 - 3)\ \text{m}^3 \times (8000 - 4000)\ \text{dyne/cm}^2.
  3. 4000 dyne/cm2=400 Pa4000\ \text{dyne/cm}^2 = 400\ \text{Pa}, so W=12×4×400=800 JW = \frac{1}{2} \times 4 \times 400 = 800\ \text{J}
  4. So the answer is (a) 800 J.
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