86) A gas is compressed in a cylinder by a movable piston to a volume one-half its original volume. During the process 300 kJ heat left the gas and internal energy remained same. The work done on gas in Nm will be

87) The more effective way of increasing efficiency of Carnot engine is to

88) Entropy change depends on

89) For reversible adiabatic process, change in entropy is

90) Isochoric process is one in which