\(n\) moles of a perfect gas undergoes a cyclic process ABCA (see figure) consisting of the following processes.
\(A\rightarrow B\) | Isothermal expansion at temperature \(T\) so that the volume is doubled from \(V_1\) to \(V_2=2V_1\) and pressure changes from \(P_1\) to \(P_2.\) |
\(B\rightarrow C\) | Isobaric compression at pressure \(P_2\) to initial volume \(V_1\). |
\(C\rightarrow A\) | Isochoric change leading to change of pressure from \(P_2\) to \(P_1\). |
Total work done in the complete cycle \(ABCA\) is:
1. \(0\)
2. \(nRT(\ln 2-\frac{1}{2})\)
3. \(nRT\ln 2\)
4. \(nRT(\ln 2+\frac{1}{2})\)
1. | \(W_1>W_2\) |
2. | \(W_1<W_2\) |
3. | \(W_1=W_2\) |
4. | \(W_1\) and \(W_2\) cannot be compared unless the temperatures are known. |
1. | \({\dfrac{3}{2}}R\) | 2. | \({\dfrac{5}{2}}R\) |
3. | \({\dfrac{1}{2}}R\) | 4. | zero |
The quantity of heat required to take a system from \(\mathrm{A}\) to \(\mathrm{C}\) through the process \(\mathrm{ABC}\) is \(20\) cal. The quantity of heat required to go from \(\mathrm{A}\) to \(\mathrm{C}\) directly is:
1. | \(300\) K | 2. | \(\dfrac{300}{2^{5/3}}\) K |
3. | \(\dfrac{300}{2^{2/3}}\) K | 4. | \(600\) K |
1. | same as the \(1^{\text{st}}\) case. |
2. | always greater than the \(1^{\text{st}}\) case. |
3. | always less than the \(1^{\text{st}}\) case. |
4. | may increase or decrease with respect to the \(1^{\text{st}}\) case. |
1. | \(\theta_A=\theta_B\) |
2. | \(\theta_A<\theta_B\) |
3. | \(\theta_A>\theta_B\) |
4. | the relationship between \(\theta_A,\theta_B\) depends on the molecular weights of \(A\) and \(B\) |
1. | zero |
2. | negative |
3. | positive |
4. | non-negative(positive or zero) |