Question

Figure shows a polytropic process for an ideal gas. The work done by the gas will be in process $AB$ is

• A. $\frac{15}{2}P_{0}V_{0}$
• B. $\frac{14}{3}P_{0}V_{0}$
• C. $8P_{0}V_{0}$
• D. Insufficient information

Answer 1

Answer: (B)

$w=\frac{1}{2}\times 6\times 10-4\times 5+4\times 5-5\times 2$
$=30-20+20-10=20J$
$w=k_{f}-k_{i}$
$20=k_{f}-25$
$k_{f}=45J$
$w=\frac{P_{2} V_{2} - P_{1} V_{1}}{1 - x}=\frac{2 P_{0} V_{0} - 16 P_{0} V_{0}}{1 - 4}$
$=\frac{14}{3}P_{0}V_{0}$