As an object of mass 60 kg approaches the bottom of a ramp, point A, its speed is 20 m/s. It goes up the frictionless plane and turns around at point B. What is the potential energy of this object at point B? Use g = 10 m/s².

Question

Quizplus · Accepted Answer

Since the ramp is frictionless, there is no change in mechanical energy. Therefore, the initial kinetic energy (K) of the object at point A is converted into potential energy (U) at point B.

K = (1/2)mv^2 = (1/2)(60 kg)(20 m/s)^2 = 12,000 J

At point B, the object is at its highest point, so all of its initial kinetic energy has been transformed into potential energy:

U = K = 12,000 J

Therefore, the potential energy of the object at point B is 12 × 10^3 J or 12,000 J. The answer is (D).

As an Object of Mass 60 Kg Approaches the Bottom