Question

A gas expands such that it is initial and final temperature are equal. Also, the process followed by the gas traces a straight line on the P-V diagram: 

(A) The temperature of the gas remains constant throughout. 

(B) The temperature of the gas first increases and then decreases.

(C) The temperature of the gas first decreases and then increases. 

(D) The straight line has a negative slopes

Answer 1

Correct option (B, D)

Explanation:

The slope of straight line can't be +ve. Since, T ∝ PV and if slope is +ve, then both P and V are increasing. Therefore, temperature will always increase.

Thus, from graph it can be seen, that temperature first increases and then decrease.