During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its temperature. The ratio of CP/CV for the gas is equal to:
1. | 4/3 | 2. | 2 |
3. | 5/3 | 4. | 3/2 |
An ideal gas goes from state \(A\) to state \(B\) via three different processes, as indicated in the \(P\text-V\) diagram. If \(Q_1,Q_2,Q_3\) indicates the heat absorbed by the gas along the three processes and \(\Delta U_1, \Delta U_2, \Delta U_3\) indicates the change in internal energy along the three processes respectively, then:
1. | \({Q}_1>{Q}_2>{Q}_3 \) and \(\Delta {U}_1=\Delta {U}_2=\Delta {U}_3\) |
2. | \({Q}_3>{Q}_2>{Q}_1\) and \(\Delta {U}_1=\Delta {U}_2=\Delta {U}_3\) |
3. | \({Q}_1={Q}_2={Q}_3\) and \(\Delta {U}_1>\Delta {U}_2>\Delta {U}_3\) |
4. | \({Q}_3>{Q}_2>{Q}_1\) and \(\Delta {U}_1>\Delta {U}_2>\Delta {U}_3\) |
In thermodynamic processes, which of the following statements is not true?
1. | In an adiabatic process, the system is insulated from the surroundings. |
2. | In an isochoric process, the pressure remains constant. |
3. | In an isothermal process, the temperature remains constant. |
4. | In an adiabatic process, \(P V^\gamma\) = constant. |
In isothermal expansion, the pressure is determined by:
1. | Temperature only |
2. | Compressibility only |
3. | Both temperature and compressibility |
4. | None of these |
Under isothermal conditions, the volumes of ideal gas A and actual gas B grow from V to 2 V. 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 specific heat of a gas in an isothermal process is:
1. | Infinite | 2. | Zero |
3. | Negative | 4. | Remains constant |
The pressure and density of a diatomic gas changes adiabatically from (P, d) to (P', d'). If , then should be:
1. | 1/128 | 2. | 32 |
3. | 128 | 4. | None of the above |
Two identical samples of a gas are allowed to expand, (i) isothermally and (ii) adiabatically. Work done will be:
1. | more in the isothermal process. |
2. | more in the adiabatic process. |
3. | equal in both processes. |
4. | none of the above. |
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 an ideal gas at an initial temperature of T K does 6R joules of work adiabatically. If the ratio of specific heats of this gas at constant pressure and at constant volume is 5/3, the final temperature of the gas will be:
1. | (T + 2.4)K | 2. | (T – 2.4)K |
3. | (T + 4)K | 4. | (T – 4)K |