1.19 A perfect gas enclosed by an insulated (upright) cylinder and piston is in equilibrium at conditions pl. 1:], T.. A weight is placed on the piston. After a number of osciliations. the motion subsides and the gas reaches a new equilibrium at conditions p2, v2, T2. Find the temperature ratio T2/ T1 in terms of the pressure ratio A = [12/ pl. Show that the Change of entropy is given by 1 _ 1 l Y/{Y-l} 1 _2,31=R.H[L] , y A Also show that, ifthe initial disturbance is small, that is. A = l + s. 8