A20 kg object is acted on by a conservative force given by F = – 3.0x – 5.0x², with Fin Newton’s and x in meters. Take the potential energy associated with the force to be zero when the object is at x = 0. (a) What is the potential energy of the system associated with the force when the object is at x = 2.0 m?

(b) If the object has a velocity of 4.0 m/s in the negative direction of the x axis when it is at x = 5.0 m, what is its speed when it passes through the origin?

(c) What are the answers to (a) and (b) if the potential energy of the system is taken to be – 8.0 J when the object is at x = 0?