16.Two cylinders A and B fitted with pistons contain equal amounts of an ideal diatomic gas at 300 K. The piston of A is free to move. The piston of B is held fixed. The same amount of heat is given to the gas in each cylinder. If the rise in temperature of the gas in A is 30 K, then the rise in temperature of the gas in B is

17.During the adiabatic expansion of 2 mol of a gas, the internal energy was found to have decreased by 100 J. The work done by the gas in this process is

18.A gas at pressure P is adiabatically compressed so that its density becomes twice that of initial value. Given that the ratio of specific heats at constant pressure and constant volume is 7/5. What will be the final pressure of the gas ?

19.A bimetal made of copper and iron strips welded together is straight at room temperature. It is held vertically in the hand so that iron strip is towards the left hand and copper strip is towards the right hand side. This bimetal is then heated by flame. The bimetal strip will

20.A system absorbs 1000 cal of heat and does 1675 J of external work. If J = 4.18 J/cal, then the change in internal energy of the system is