A spring of force constant 10 N/m has an initial stretch 0.20 m. In changing the stretch to 0.25 m, the increase in potential energy is about-
Potential energy of object at initial stretch
P1 = 12k×2 = 12×10×0.2×0.2 = 0.2 J
Potential energy of object at changed stretch
P2 = 12k×2 = 12×10×0.25×0.25 = 0.3 J
difference in potential energy = P2 − P1 = 0.3 J − 0.2 J = 0.1 J