Q. No.The temperature inside a refrigerator (reversible process) is t2oC and the room temperature is t1oC. The amount of heat delivered to the room for each joule of
electrical energy consumed, ideally, will be:
1.
2.
3.
4.
The volume (\(V\)) of a monatomic gas varies with its temperature (\(T\)), as shown in the graph. The ratio of work done by the gas to the heat absorbed by it when it undergoes a change from state \(\mathrm{A}\) to state \(\mathrm{B}\) will be:
| 1. | \(2 \over 5\) | 2. | \(2 \over 3\) |
| 3. | \(1 \over 3\) | 4. | \(2 \over 7\) |
The efficiency of an ideal heat engine (Carnot heat engine) working between the freezing point and boiling point of water is:
1. \(26.8\%\)
2. \(20\%\)
3. \(6.25\%\)
4. \(12.5\%\)
A gas is compressed isothermally to half its initial volume. The same gas is compressed separately through an adiabatic process until its volume is again reduced to half. Then,
| 1. | compressing the gas through an adiabatic process will require more work to be done. |
| 2. | compressing the gas isothermally or adiabatically will require the same amount of work. |
| 3. | which of the case (whether compression through isothermal or through the adiabatic process) requires more work will depend upon the atomicity of the gas. |
| 4. | compressing the gas isothermally will require more work to be done. |
(Take, 1 cal= 4.2 Joules)
1. 23.65 W
2. 236.5 W
3. 2365 W
4. 2.365 W
An ideal gas is compressed to half its initial volume using several processes. Which of the processes results in the maximum work done on the gas?
1. adiabatic
2. isobaric
3. isochoric
4. isothermal
The coefficient of performance of a refrigerator is \(5.\) If the temperature inside the freezer is \(-20^\circ \text{C},\) the temperature of the surroundings to which it rejects heat is:
1. \(31^\circ \text{C}\)
2. \(41^\circ \text{C}\)
3. \(11^\circ \text{C}\)
4. \(21^\circ \text{C}\)
The figure below shows two paths that may be taken by gas to go from state \(A\) to state \(C\).
In process \(AB\), \(400~\text{J}\) of heat is added to the system, and in process \(BC\), \(100~\text{J}\) of heat is added to the system. The heat absorbed by the system in the process \(AC\) will be:
1. \(380~\text{J}\)
2. \(500~\text{J}\)
3. \(460~\text{J}\)
4. \(300~\text{J}\)
A Carnot engine, having an efficiency of = as a heat engine, is used as a refrigerator. If the work done on the system is \(10\) J, the amount of energy absorbed from the reservoir at a lower temperature is:
1. \(100\) J
2. \(99\) J
3. \(90\) J
4. \(1\) J
A monoatomic gas at a pressure \(P\), having a volume \(V\), expands isothermally to a volume \(2V\) and then adiabatically to a volume \(16V\). The final pressure of the gas is: \(\left(\text{Take:}~ \gamma = \frac{5}{3} \right)\)
| 1. | \(64 ~P\) | 2. | \(32~P\) |
| 3. | \(\frac{P}{64}\) | 4. | \(16~P\) |
© 2024 GoodEd Technologies Pvt. Ltd.