The volume versus temperature graphs for a given mass of an ideal gas are shown in the figure at two different values of constant pressure. What can be inferred about relation between P1P1 and P2P2?

                  
1. P1>P2P1>P2
2. P1=P2P1=P2
3. P1<P2P1<P2
4. data is insufficient

Hint: The slope of the V-T graph gives the pressure.

Step 1: Find the slope of the two graphs.
We know for an ideal gas,
                        pV=nRTV=(nRP)TpV=nRTV=(nRP)T
Slope of the V— T graph, m=dVdT=nRPm=dVdT=nRP         [m = slope of V-T graph]
             m1P             m1P                                                        [ nR = constant]
             P1m
Step 2: Find the relation between two pressures.
hence,     P1P2=m2m1<1                 [P=pressure]
where m1 is the slope of the graph corresponding to P1 and similarly m2 is the slope corresponding to P2.
                  P1>P2
Hence, option (1) is the correct answer.