Helum gas is used as working substance in an engine working on a thermodynamic cycle A – B – C – D – A. Process AB is isobaric, BC is adiabatic compression. During process CD, pressure is increased keeping the volume constant and DA is an isothermal process. The gas has maximum volume at A and the ratio of maximum to minimum volume during the entire cycle is `8sqrt(2)` . Also, the ratio of maximum to minimum absolute temperature is 4.
(a) Represent the cycle on a P – V diagram.
(b) Calculate efficiency of the cycle in percentage if it is used as an engine. [Take ln 2 = 0.693]

Answer

`(a) `(##IJA_PHY_V02_C04_E01_056_S01##)`
(b) 41%