Ms Png works on a piston-cylinder system which contains 0.05 m3 of nitrogen gas initially at 200 kPa. At this state, a linear spring that has a spring constant of 150 kN/m is touching the piston, but no force is exerting on it. Heat is then transferred to the nitrogen gas, causing the piston to rise and to compress the spring until the volume inside the cylinder increases to 0.25 m3. a) Determine the final pressure inside the cylinder. b) Sketch the system on a P – V diagram. c) Calculate the total work done of the system. d) Deduce the work done against the spring to compress it. Given cross-sectional area of the piston = 0.25 m2 Force applied by linear spring, F = kx k = spring constant x = displacement

Ms Png works on a piston-cylinder system which contains 0.05 m3 of nitrogen gas
initially at 200 kPa. At this state, a linear spring that has a spring constant of 150
kN/m is touching the piston, but no force is exerting on it. Heat is then transferred
to the nitrogen gas, causing the piston to rise and to compress the spring until the
volume inside the cylinder increases to 0.25 m3.
a) Determine the final pressure inside the cylinder.
b) Sketch the system on a P – V diagram.
c) Calculate the total work done of the system.
d) Deduce the work done against the spring to compress it.
Given cross-sectional area of the piston = 0.25 m2
Force applied by linear spring, F = kx
k = spring constant
x = displacement of the piston/spring