Under isothermal conditions, the volumes of ideal gas \(A\) and actual gas \(B\) grow from \(V\) to \(2V\). The increase in internal energy:

1.	will be the same in both \(A\) and \(B\).
2.	will be zero in both the gases.
3.	of \(B\) will be more than that of \(A\).
4.	of \(A\) will be more than that of \(B\).

The work done in an adiabatic change in a gas depends only on

(1) Change is pressure

(2) Change is volume

(3) Change in temperature

(4) None of the above

The pressure and density of a diatomic gas $(\gamma =7/5)$ changes adiabatically from (P, d) to (P', d'). If $\frac{d\text{'}}{d}=32$, then $\frac{P\text{'}}{P}$ should be: 

Air in a cylinder is suddenly compressed by a piston, which is then maintained at the same position. With the passage of time 

In an adiabatic expansion of a gas, if the initial and final temperatures are \(T_1\) and \(T_2\), respectively, then the change in internal energy of the gas is:
1. \(\frac{nR}{\gamma-1}(T_2-T_1)\)
2. \(\frac{nR}{\gamma-1}(T_1-T_2)\)
3. \(nR ~(T_1-T_2)\)
4. Zero

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

(1) $C_V(T_i-T_f)$

(2) $C_P(T_i-T_f)$

(3) $\frac{1}{2}(C_P+C_V)(Ti-T_f)$

(4) $(C_P-C_V)(T_i-T_f)$

Unit mass of a liquid with volume V₁ is completely changed into a gas of volume V₂ at a constant external pressure P and temperature T. If the latent heat of evaporation for the given mass is L, then the increase in the internal energy of the system is -

(1) Zero

(2) $P(V_2-V_1)$

(3) $L-P(V_2-V_1)$

(4) L

If the door of a refrigerator is kept open, then which of the following is true ?

1. Room is cooled

2. Room is heated

3. Room is either cooled or heated

4. Room is neither cooled nor heated

In a cyclic process, the internal energy of the gas:

The efficiency of Carnot's engine operating between reservoirs, maintained at temperatures 27°C and –123°C, is 

(1) 50%

(2) 24%

(3) 0.75%

(4) 0.4%