Chapter 2
Q. 2.5
A cylinder contains compressed helium gas. It is used to inflate rubber balloon to a volume of 0.8m³. If the atmospheric pressure is 1 bar, find the work done upon the atmosphere by the balloon. Sketch the system before and after the process.
Step-by-Step
Verified Solution
The cylinder – balloon system is shown in Fig. 2.21.
Net displacement work done,
\begin{aligned}W_{\text {net }} &=\int\limits_{\text {cylinder }} p \cdot d V+\int\limits_{\text {balloon }} p \cdot d V \\&=0+1 \times 10^2 \times 0.8=80 \ kJ\end{aligned}
No work is done on the cylinder as its volume is constant.
