In a thermodynamic process,the pressure of a fixed mass of a gas is changed in such a manner that the gas releases $20 \ J$ of heat and $8 \ J$ of work is done on the gas. If the initial internal energy of the gas was $30 \ J$,the final internal energy will be ...... $J$.

Why does a gas get heated on compression?

$1\,g$ of water at $100\,^{\circ}C$ and $10^5\,Pa$ pressure converts into $1841\,cm^3$ of steam at constant temperature and pressure. If the latent heat of vaporization of water is $2250\,J/g$,the change in internal energy of water in this process is ..... $J$.

$A$ cylinder with a piston of unit cross-sectional area contains one mole of an ideal gas as shown in the figure. $A$ spring of unstretched length $L$ and spring constant $K$ is connected between the piston and the bottom of the cylinder. Initially, the spring is unstretched and the gas is in equilibrium. When an amount of heat $Q$ is supplied to the gas, its volume changes from $V_0$ to $V_1$. Find:
$(a)$ The initial pressure of the system.
$(b)$ The final pressure of the system.
$(c)$ Using the first law of thermodynamics, find the relation between $Q, V_0, V_1, P_a$ and $K$.

During the process $A \rightarrow B \rightarrow C$,the work done is $50 \, J$ and the heat supplied is $20 \, cal$. Find the change in internal energy between $A$ and $C$ in $J$. (in $, J$)

In a given process,for an ideal gas,$\Delta W = 0$ and $\Delta Q < 0$. Then,for the gas,