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

One mole of an ideal gas expands at a constant temperature of \(300~\text{K}\) from an initial volume of \(10\) litres to a final volume of \(20\) litres. The work done in expanding the gas is equal to:
(\(R = 8.31\) J/mole-K)
1. \(750~\text{J}\)
2. \(1728~\text{J}\)
3. \(1500~\text{J}\)
4. \(3456~\text{J}\)

The pressure of a monoatomic gas increases linearly from $\mathrm{}$\(4\times 10^5~\text{N/m}^2\) to $\mathrm{}$\(8\times 10^5~\text{N/m}^2\) when its volume increases from \(0.2 ~\text m^3\) to \(0.5 ~\text m^3.\) The work done by the gas is:
1. \(2 . 8 \times10^{5}~\text J\)
2. \(1 . 8 \times10^{6}~\text J\)
3. \(1 . 8 \times10^{5}~\text J\)
4. \(1 . 8 \times10^{2}~\text J\)$\mathrm{}$

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 \(A\) to state \(B\) will be:
             

The temperature inside a refrigerator (reversible process) is t₂^oC and the room temperature is t₁^oC. The amount of heat delivered to the room for each joule of electrical energy consumed, ideally, will be:

1.  $\frac{t_1}{t_1-t_2}$

2.  $\frac{t_1+273}{t_1-t_2}$

3.  $\frac{t_2+273}{t_1+t_2}$

4.  $\frac{t_1+t_2}{t_1+273}$