GATE 2016 ME (ME1) – Question 56
An ideal gas undergoes a reversible process with pressure varying linearly with volume, from p₁ = 100 kPa, V₁ = 0.2 m³ to p₂ = 200 kPa, V₂ = 0.1 m³. The gas constant is R = 0.275 kJ/kg K. The magnitude of work required is ______ kJ.
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: 14.75 to 15.25
Explanation
Boundary work is the area under p(V). For a straight line it equals average pressure times volume change: Wby=(100+200)/2·(0.1−0.2)=−15kJ. The negative sign indicates compression work input. Requested magnitude is therefore **15kJ**; endpoint pV equality does not make the intervening path isothermal.