What is an isochoric process and cyclic process ? Write the first law of thermodynamics for an ideal gas.

$P-V$ plots for two gases during adiabatic process are shown in the figure. Plots $1$ and $2$ should correspond respectively to

If $\Delta U$ and $\Delta W$ represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true?

One mole of helium is adiabatically expanded from its initial state $({P_i},{V_i},{T_i})$ to its final state $({P_f},{V_f},{T_f})$. The decrease in the internal energy associated with this expansion is equal to

Following figure shows on adiabatic cylindrical container of volume ${V_0}$ divided by an adiabatic smooth piston (area of cross-section = $A$ ) in two equal parts. An ideal gas $({C_P}/{C_V} = \gamma )$ is at pressure $P_1$ and temperature $T_1$ in left part and gas at pressure $P_2$ and temperature $T_2$ in right part. The piston is slowly displaced and released at a position where it can stay in equilibrium. The final pressure of the two parts will be (Suppose $ x$ = displacement of the piston)

Adiabatic modulus of elasticity of a gas is $2.1 \times {10^5}N/{m^2}.$ What will be its isothermal modulus of elasticity $\left( {\frac{{{C_p}}}{{{C_v}}} = 1.4} \right)$