Question

A gas at pressure $6 ×10^5\, N\, m^{-2}$ and volume $1\, m^3$ and its pressure falls to $4 × 10^5\, N \,m^{-2}$. When its volume is $3\, m^3$. Given that the indicator diagram is a straight line, work done by the system is

• A. $6 × 10^5 \,J$
• B. $3 × 10^5 \,J$
• C. $4 × 10^5 \,J$
• D. $10 × 10^5 \,J$

Answer 1

Answer: (D)

Work done by the system
= area under $P - V$ diagram
= area of rectangle $BCDE +$ area of $ΔABC$
$=4\times10^{5}\times2+\frac{2\times10^{5}\times2}{2}$
$W=10\times10^{5}\,J$