Q. Two moles of helium gas expanded isothermally and irreversible at 27$℃$ from volume $1\ dm^{3}$ to $1\ m^{3}$ at constant pressure of 100 k Pa. Calculate the work done.
A) 99900 kJ
B) 99900 J
C) 34464.65 kJ
D) 34464.65 J
Explanation
(b)
$W = - p\mathrm{\Delta}V$
Given, $p + 100kPa = 10^{5}\ Pa,$
$V_{1} = 1dm^{3} = 10^{- 3}m^{3},V_{2} = 1m^{3}$
$W = 10^{5} \times \left( 1 - 10^{- 3} \right)$ J
$\therefore\ \ \ \ \ \ \ \ \ W = 99900$ J
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.