A gas undergoes the change in its state from position A to position B via three different paths as shown in figure. Select the correct alternative(s)

 

 

 

a) Internal energy (U) depends only on the initial and final status. Hence, $\Delta U$ will be same in all the three paths.

B) In all the three paths work done by the gas is positive (volume is increasing) and the product PV is also increasing means temperature is also increasing. So, $\Delta U$ is also positive.

C) T is increasing. Therefore, internal energy is also increasing so, from first law of thermodynamics heat will be absorbed by the gas. Further area under P-V graph is maximum in path 1 while $\Delta U$ is same for all three paths. Therefore, heat absorbed by the gas is maximum in path1.

D) For temperature of the gas we can see the product PV which first increases in path 1 but whether it is decreasing or increasing later on we cannot say anything about it unless the exact values are known to us