First law of thermodynamics is represented by

$A$ system is taken from state $A$ to state $B$ along two different paths. The heat absorbed and work done by the system along these two paths are $Q_1, Q_2$ and $W_1, W_2$ respectively,then

$A$ gas is compressed at a constant pressure of $50 \,N/m^2$ from a volume of $10 \,m^3$ to a volume of $4 \,m^3$. Energy of $100 \,J$ is then added to the gas by heating. Its internal energy is

When a system is taken from state $i$ to state $f$ along the path $iaf$,it is found that $Q = 50 \ cal$ and $W = 20 \ cal$. Along the path $ibf$,$Q = 36 \ cal$. The work done $W$ along the path $ibf$ is ....... $cal$.

If a system undergoes contraction of volume,then the work done by the system will be:

When unit mass of water boils to become steam at $100\,^{\circ}C$,it absorbs $Q$ amount of heat. The densities of water and steam at $100\,^{\circ}C$ are $\rho_1$ and $\rho_2$ respectively and the atmospheric pressure is $p_0$. The increase in internal energy of the water is: