Assertion (A): | If the efficiency of the engine is \(\frac1n,\) then the coefficient of performance of the reversed cycle working as a refrigerator is \(n-1\). |
Reason (R): | \(1-\frac{T_{\text{low}}}{T_{\text{high}}},\) while the coefficient of performance of the reversed cycle is \(\frac{T_{\text{low}}}{T_{\text{high}~-~T_{\text{low}}}}\). | The efficiency of Carnot's cycle is
1. | (A) is true but (R) is false. |
2. | (A) is false but (R) is true. |
3. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
4. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
1. | \(4\) | 2. | \(1\) |
3. | \(2\) | 4. | \(3\) |
Assertion (A): | It is not possible for a system, unaided by an external agency to transfer heat from a body at a lower temperature to another at a higher temperature. |
Reason (R): | It is not possible to violate the second law of thermodynamics. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |
Statement (A): | Heat is not a state function. |
Statement (B): | Heat supplied to a system is a path function. |
1. | Both statements (A) and (B) are true. |
2. | Both statements (A) and (B) are false. |
3. | Only statement (A) is true. |
4. | Only statement (B) is true. |
1. | The magnitude of the work done by the gas is \(RT_{0}\ln 2\). |
2. | Work done by the gas is \(V_{0}T_{0}.\) |
3. | Net work done by the gas is zero. |
4. | Work done by the gas is \(2RT_{0}\ln2\). |
1. | The change in internal energy in the process \(BC\) is \(-500R.\) |
2. | The change in internal energy in the whole cyclic process is \(250R.\) |
3. | The change in internal energy in the process \(CA\) is \(700R.\) |
4. | The change in internal energy in the process \(AB\) is \(-350R.\) |
Statement I: | Molar heat capacity at constant pressure for all diatomic gases is the same. |
Statement II: | The specific heat capacity at constant pressure of all diatomic ideal gases is the same. |
1. | only (I) is correct |
2. | only (II) is correct |
3. | both (I) and (II) are correct |
4. | none of them are correct |
Figure shows P-T diagram for given mass of an ideal gas for the process A→B. During this process, density of the gas is
1. Decreasing
2. Increasing
3. Constant
4. First decreasing then increasing
Consider the following two statements.
(A): | If heat is added to a system, its temperature must increase. |
(B): | If positive work is done by a system in a thermodynamic process, its volume must increase. |
1. | Both A and B are correct. |
2. | A is correct but B is wrong. |
3. | B is correct but A is wrong. |
4. | Both A and B are wrong. |
Match the thermodynamic processes taking place in a system with the correct conditions. In the table, \(\Delta Q\) is the heat supplied, \(\Delta W\) is the work done and \(\Delta U\) is the change in internal energy of the system.
Process | Condition | ||
(I) | Adiabatic | (A) | \(\Delta W=0\) |
(II) | Isothermal | (B) | \(\Delta Q=0\) |
(III) | Isochoric | (C) | \(\Delta U\neq0, \Delta W\neq0,\Delta Q\neq0\) |
(IV) | Isobaric | (D) | \(\Delta U=0\) |
1. | (I) – (B), (II) – (A), (III) – (D), (IV) – (C) |
2. | (I) – (A), (II) – (A), (III) – (B), (IV) – (C) |
3. | (I) – (A), (II) – (B), (III) – (D), (IV) – (D) |
4. | (I) – (B), (II) – (D), (III) – (A), (IV) – (C) |