During an adiabatic compression of 5 moles of a gas, 250 J of work was done. The change in the internal energy will be 

In an adiabatic process, $\mathrm{dQ}=0$. Therefore, $\mathrm{dU}=-\mathrm{dW},$ i.e. change in internal energy = work done. Since work is done on the gas dW is negative. Hence $\mathrm{dU}=-(-250)=250\mathrm{J}$. Thus the internal energy increases by 250 J. Hence the correct choice is (3).