Q: Which of the processes described below are irreversible ?
(a) The increase in temperature of an iron rod by hammering it
(b) A gas in a small container at a temperature T_1 is brought in contact with a big reservoir at a higher temperature T_2 which increase the temperature of the gas
(c) A quasi-static isothermal expansion of an ideal gas in cylinder fitted with a frictionless piston
(d) An ideal gas is enclosed in a piston cylinder arrangement with adiabatic walls. A weight w is added to the piston, resulting in compression of gas
Ans: (a) , (b) & ()