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. \(12.5\%\)
1. \(26.8\%\)
2. \(20\%\)
3. \(6.25\%\)
4. \(12.5\%\)
Reason Dissipative effects cannot be eliminated.
1. If both assertion and reason are true and reason explain the assertion.
2. If both the assertion and reason are true but reason does not explain the assertion.
3. If assertion is true but reason is false.
4. If assertion is false but reason is true.
(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
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
| 1. | \(64P\) | 2. | \(32P\) |
| 3. | \(\frac{P}{64}\) | 4. | \(16P\) |
A thermodynamic system undergoes a cyclic process \(ABCDA\) as shown in Fig. The work done by the system in the cycle is:
1. \( P_0 V_0 \)
2. \( 2 P_0 V_0 \)
3. \( \frac{P_0 V_0}{2} \)
4. zero
| 1. | \(1000~\text{J}\) | 2. | zero |
| 3. | \(-2000~\text{J}\) | 4. | \(2000~\text{J}\) |
| 1. | \(\dfrac{R}{\gamma -1}\) | 2. | \(\dfrac{\gamma -1}{R}\) |
| 3. | \(\gamma R \) | 4. | \(\dfrac{\left ( \gamma -1 \right )R}{\left ( \gamma +1 \right )}\) |
A thermodynamic system is taken through the cycle \(ABCD\) as shown in the figure. Heat rejected by the gas during the cycle is:
1. \(2 {PV}\)
2. \(4{PV}\)
3. \(\frac{1}{2}{PV}\)
4. \(PV\)
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