One mole of an ideal gas undergoes a cyclic change ABCD. Calculate from the diagram. (P is in atm, and V in litre) (i) Work done along AB, BC, CD and DA. (ii) What is the net work done in the process ? (iii). What is the efficiency of the process ? (iv) What is the net change in internal energy of the gas ? Given 1 atm = 1. 01 xx 10 ^(5) Nm ^(-2)

One mole of an ideal gas undergoes a cyclic change ABCD. Calculate fro

1.	One mole of an ideal gas undergoes a cyclic change ABCD. Calculate from the diagram. (P is in atm, and V in litre) (i) Work done along AB, BC, CD and DA. (ii) What is the net work done in the process ? (iii). What is the efficiency of the process ? (iv) What is the net change in internal energy of the gas ? Given 1 atm = 1. 01 xx 10 ^(5) Nm ^(-2)
Answer» Solution :(i) Work done ALONG AB= Pressure `xx` Change in volume = PdV `= 5 xx 1.01 xx 10 ^(5) xx 2 xx 10 ^(-3)` `= 1010` Joule Work done along `BC = 0` because DV =0 Word done along `CD = PdV` `= 2 xx 1.01 xx 10 ^(5) xx (1-3) xx 10 ^(-)` `=- 404 J ` Work done along `DA = PdV` =0, Because `dV =0` (ii) Net word done `=1010 - 404 = 6060 J` (iii) Efficiency `= ("Useful work")/("Total work") xx 100` `= ( 606)/(1010) xx 100 = 60%` (IV) Net change in interna energy of the gas =0, because the process is a cyclic process.