In the case of free expansion, when a sample of gas expands suddenly, the change in internal energy of the gas will be:
1. Positive
2. Negative
3. Zero
4. May be positive or negative
The work done for the given process AB is:
1. 6
2. 5
3. 3
4. 2
The efficiency of a Carnot heat engine working between the temperatures \(27^{\circ}\mathrm{C}\) and \(227^{\circ}\mathrm{C}\) is:
1. 0.1
2. 0.6
3. 0.2
4. 0.4
Work done during the given cycle is:
1. 4
2. 2
3.
4.
The cyclic process of 2 moles of diatomic gas is shown in the figure. Which of the following statements is correct?
1. | Process BC is an isothermal compression. |
2. | Work done in the process CA is \(4 R T_0\) |
3. | Work done in the process AB is zero. |
4. | All of these |
An ideal gas is enclosed in an insulated cylinder. The piston is frictionless and attached to an ideal spring. When the gas is heated, then:
1. | the work is done against the spring only. |
2. | the work is done against the atmospheric pressure only. |
3. | the internal energy of gas increases. |
4. | the work is equal to the heat supplied. |
If a gas undergoes the change in its thermodynamic state from A to B via two different paths, as shown in the given pressure (P) versus volume (V) graph, then:
1. | the temperature of the gas decreases in path 1 from A to B. |
2. | the heat absorbed by the gas in path 1 is greater than in path 2. |
3. | the heat absorbed by the gas in path 2 is greater than in path 1. |
4. | the change in internal energy in path 1 is greater than in path 2. |
The PV diagram of an ideal gas is shown in the figure. The work done by the gas in the process is given by:
1. | \(\frac{9}{2}P_0V_0\) | 2. | \(\frac{15}{2}P_0V_0\) |
3. | \(\frac{13}{2}P_0V_0\) | 4. | \(\frac{3}{2}P_0V_0\) |
A pressure (P) versus volume (V) graph is obtained for an ideal gas from state A to State B (as shown in the figure below). Which of the following is the correct statement?
1. | The temperature of gas increases continuously. |
2. | The temperature of gas decreases continuously. |
3. | The temperature first increases, then decreases. |
4. | The temperature first decreases, then increases |
When the sink temperature is kept at 400 K, the efficiency of a Carnot engine is 50%. While keeping the source temperature constant, by how much should we reduce the sink temperature to increase the efficiency to 60%?
1. | 80 K | 2. | 70 K |
3. | 320 K | 4. | 240 K |