A cylinder contains 1.5 kg of steam at 100 kPa 200°C. At this state a nonlinear spring, with F = kx2, is touching the piston but exerts no force on it. Heat is now transferred to the water causing the piston to rise. If the spring constant is 500kN/m2 and the area of the piston is 0.05 m2 determine the work done when the pressure inside the cylinder reaches 500 kPa.