Q. No.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
| 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. | \(\dfrac{P_0 V_0}{2} \) | 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. | \(\dfrac{\left ( \gamma -1 \right )R}{\left ( \gamma +1 \right )}\) |
| 1. | \(2 {PV}\) | 2. | \(4{PV}\) |
| 3. | \(\dfrac{1}{2}{PV}\) | 4. | \(PV\) |
One mole of an ideal gas goes from an initial state \(A\) to the final state \(B\) with two processes. It first undergoes isothermal expansion from volume \(V\) to \(3V\) and then its volume is reduced from \(3V\) to \(V\) at constant pressure. The correct \((P-V)\) diagram representing the two processes is:
| 1. |  |
2. |  |
| 3. |  |
4. |  |
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