One mole of an ideal gas is taken from state A to state B by  three different processes (a) ACB, (b) ADB and (c) AEB as shown in the P-V diagram. The heat absorbed by the gas is :

less in (c) and in (b)

Heat absorbed by gas in three processes is given by : 

\(Q_{ACB} = \Delta U + W_{ACB}\)

\(Q_{ADB} = \Delta U\)

\(Q_{AEB} = \Delta U + W_{AEB}\)

The change in internal energy in all the three cases is same and W_ACB is positive, W_AEB is negative.

Hence, Q_ACB > Q_ADB > Q_AEB