• question_answer An ideal monoatomic gas is confined in a cylinder, fitted with piston, which is connected to spring as shown in figure. The gas is heated by a-small electric heater until the piston moves out slowly by 0.1 m. Find the work done by the gas. Spring constant = 8000 N/m,-piston area $=8\times {{10}^{-3}}{{\text{m}}^{2}}$ atmospheric pressure $={{10}^{5}}Pa$.               A) 40 J B) 80 J C) 120 J D) 60 J

 [c]Work done $=\int_{0}^{{{x}_{0}}}{{{p}_{0}}Axdx}+\frac{kx_{0}^{2}}{2}$ $={{p}_{0}}A{{x}_{0}}+\frac{kx_{0}^{2}}{2}=80+40=120J$ where p = pressure of gas, ${{p}_{0}}=$ atmospheric pressure k = spring constant ${{x}_{0}}=$ compression in spring.