$A$ diatomic gas has an initial internal energy of $80 cal$. $A$ work of $18 cal$ is done on the gas and the gas releases heat energy of $42 J$. The final internal energy of the gas is

The first law of thermodynamics states that:

If heat given to a system is $6 \, kcal$ and work done is $6 \, kJ$,then the change in internal energy is ....... $kJ$.

When $2 \ kg$ of water is boiled at atmospheric pressure,it converts into steam. The volume increases from $2 \times 10^{-3} \ m^3$ to $3.34 \ m^3$. The work done by the system is ....... $kJ$.

When heat energy of $1500 \; J$ is supplied to a gas at a constant pressure of $2.1 \times 10^5 \; N/m^2$,its volume increases by $2.5 \times 10^{-3} \; m^3$. The increase in the internal energy of the gas in Joules is ...... $J$.

Which of the following does not follow the first law of thermodynamics? $(W = \text{work}, Q = \text{heat}, \Delta U = \text{change in internal energy})$