Preston pushes a wheelbarrow weighing 480 N to the top of a 45.0-m ramp,inclined at 22.0° with the horizontal,and leaves it.Tamara accidentally bumps the wheelbarrow.It slides back down the ramp,during which an 85.0-N frictional force acts on it over the 45.0 m.What is the wheelbarrow's kinetic energy at the bottom at of the ramp? (g = 9.8 m/s²) A)1.4E+3 J B)1.6E+4 J C)1.2E+4 J D)8.1E+3 J E)4.3E+3 J

Question

Quizplus · Accepted Answer

The gravitational potential energy at the top is converted into kinetic energy at the bottom minus the work done against friction. The potential energy is mgh = 480 N * 45.0 m * sin(22.0°). The work done against friction is 85.0 N * 45.0 m. Subtract the work done against friction from the potential energy to find the kinetic energy at the bottom.

Preston Pushes a Wheelbarrow Weighing 480 N to the Top