Question

A child and sled with a combined mass of 50.0 kg slide down a frictionless hill. if the sled starts from rest and has a speed of 12.0 m/s at the bottom, what is the height of the hill?

Answer 1

Using the kinematic equation: (final speed)^2 = (initial speed)^2 + 2 * acceleration * distance (12)^2 = (0)^2 + 2 * acceleration * distance The child and sled are accelerating under gravity which exerts a force down the hill, so acceleration = g = 9.8 m/s^2 in the "down" direction. 144 = 2 * 9.8 * "down" distance (height of the hill) height of the hill = 7.35m