A gas under constant pressure of 4.5 x 105 Pa, when subjected to 800 kJ of heat, changes the volume from 0.5 m3 tp 2.0 m3. The change in internal energy of the gas is :
Answer & explanation
Correct answer: option 4
P = 4.5 x 105 Pa;
dQ = 800 kJ
V1 = 0.5 m3 ; V2 = 2 m3
dW = P(V2 - V1) = 4.5 x 105 (2 x 0.5)
= 6.75 x 105 J
Change in internal energy : dU = dQ - dW
dU = 800 x 103 - 6.75 x 105
= 1.25 x 105 J