$A$ gas can be taken from $A$ to $B$ via two different processes $ACB$ and $ADB$. When path $ACB$ is used,$60 \, J$ of heat flows into the system and $30 \, J$ of work is done by the system. If path $ADB$ is used,the work done by the system is $10 \, J$. The heat flow into the system in path $ADB$ is ..... $J$.

$1 \ cc$ of water at its boiling point $(100^{\circ} \ C)$ is converted into steam by supplying $540 \ \text{calories}$ of heat. The volume of steam is $1671 \ cc$. If atmospheric pressure is $1.013 \times 10^5 \ \text{Nm}^{-2}$ and $J = 4.18 \ \text{joule/cal}$, the approximate value of heat required to overcome the molecular attraction is ........ $\text{cal}$.

$A$ thermodynamic system is changed from state $(P_1, V_1)$ to $(P_2, V_2)$ by two different processes. The quantity which will remain the same is

Calculate the change in internal energy when $1 \,g$ of water is converted into steam at atmospheric pressure $(1.013 \times 10^{5} \,Pa)$. Given the latent heat of vaporisation is $2256 \,J/g$, the volume of $1 \,g$ of water is $1 \,cm^{3}$, and the volume of $1 \,g$ of steam is $1671 \,cm^{3}$.

Given below are two statements. One is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$ : If $dQ$ and $dW$ represent the heat supplied to the system and the work done on the system respectively,then according to the first law of thermodynamics $dQ = dU - dW$.
Reason $R$ : The first law of thermodynamics is based on the law of conservation of energy.
In the light of the above statements,choose the correct answer from the options given below:

Why does a gas get heated on compression?