Helium gas goes through a cycle A B C D A (consisting of two isochoric and two isobaric lines) as shown in figure. The efficiency of this cycle is approximately

Step-by-step solution

Helium is mono atomic gas, for which C V = 3 2 R . C p = 5 2 R Work done by the gas in one complete cycle W = area A B C D A = p 0 V 0 From A to B , Heat given to gas = n C V Δ T = 1 × 3 2 R × Δ T = 3 2 V 0 Δ p = 3 2 V 0 p 0 From B to C , heat given to gas = n C p Δ T = 1 × 5 2 R × Δ T = 5 2 2 p 0 Δ V = 5 p 0 V 0 Efficiency of cycle =   Work   done   by   the   gas / cycle     Total   heat   given   to   gas / c