A mass is attached to an unusual spring-like object, which has a position- dependent restoring force of F(x) = -(8.0 N/m³)x³ – (1.2 N/m³)x³ a. What is the work done to move the mass from equilibrium to x=0.5 m. b. What is the potential energy of the object at x=0.5m (taking equilibrium as the reference point).

A mass of 0.25 kg is attached to a spring whose spring constant is k = 25 N/m. The spring is compressed 0.35 m on a frictionless surface and released from rest. At what location is the kinetic energy at a maximum, what is the amount of kinetic energy, and what is the velocity of the mass at that point?

A horizontal spring attached to a wall has a force constant of k = 870 N/m. A block of mass m = 1.30 kg is attached to the spring and rests on a frictionless, horizontal surface as in the figure below. wwwwwwwwww x= x;/2 x= x; i (a) The block is pulled to a position x; = 6.20 cm from equilibrium and released. Find the potential energy stored in the spring when the block is 6.20 cm from equilibrium. J m x = 0 (b) Find the speed of the block as it passes through the equilibrium position. m/s (c) What is the speed of the block when it is at a position x;/2 = 3.10 cm? m/s

1. An object with m = 2.6 kg is on top of a hill and is pressed against spring with k = 300 N/m. The spring is compressed by x = 0.55 m. The hill is 2.5 m high. The object is released and after the spring is decompressed it slides down the hill to the bottom. It does experience riction which does work of W = -92 J. At the bottom of the hill what is the object's kinetic nergy and what is its velocity? %3D %3D