Question

A frictionless piston-cylinder based enclosure contains some amount of gas at a pressure of $400$ $kPa$. The heat is transferred to the gas at constant pressure in a quasi-static process. The piston moves up slowly through a height of $10cm$. If the piston has a cross-sectional area of $0.3m^2$, the work done by the gas in this process is:

• A. $6kJ$
• B. $12kJ$
• C. $7.5kJ$
• D. $24kJ$

Answer 1

Answer: (B)

$12kJ$

$W_{constantpressure}=p\times \Delta V=400\times {10}^3\times 0.3\times 10\times {10}^{-2}$
$=400\times 10\times 3$
$=12000J$

$=12kJ$