Thermodynamics Question 16
Question 16 - 31 January - Shift 1
The pressure of a gas changes linearly with volume from $A$ to $B$ as shown in figure. If no heat is supplied to or extracted from the gas then change in the internal energy of the gas will be
(1) $6 J$
(2) Zero
(3) $-4.5 J$
(4) $4.5 J$
Show Answer
Answer: (4)
Solution:
Formula: First law of thermodynamics
As $\Delta q=0$
$\Delta u=-W$
$W=\int PdV$
$\Delta u=-W=30 \times 10^{3} \times 150 \times 10^{-6}$
$=4500 \times 10^{-3}$
$=4.5 J$
