A vertical cylinder with heat-conducting walls is closed at the bottom and is fitted with a smooth light piston. It contains one mole of an ideal gas. The temperature of the gas is always equal to the surrounding’s temperature, T₀. The piston is moved up slowly to increase the volume of the gas to η times. Which of the following is incorrect?
Options

Question

A vertical cylinder with heat-conducting walls is closed at the bottom and is fitted with a smooth light piston. It contains one mole of an ideal gas. The temperature of the gas is always equal to the surrounding’s temperature, T₀. The piston is moved up slowly to increase the volume of the gas to η times. Which of the following is incorrect?

Options

G1 Physics · Accepted Answer

Use the first law Q=ΔU+W (W by the gas), ΔU=nCᵥΔT for an ideal gas, and the appropriate process relation. For Carnot devices, let T₁ be the cold-reservoir temperature and T₂ be the hot-reservoir temperature; η=1−T₁/T₂ and COP=T₁/(T₂−T₁). Evaluating the given data/statements gives D: The final pressure of the gas is 1 ( 1) η− times its initial pressure.. Therefore the correct answer is D.