Preston pushes a wheelbarrow weighing 500 N to the top of a 50.0-m ramp,inclined at 20.0° with the horizontal and leaves it.Tamara accidentally bumps the wheelbarrow.It slides back down the ramp,during which a 60.0-N frictional force acts on it over the 50.0 m.What is the wheelbarrow's kinetic energy at the bottom at of the ramp? (g = 9.8 m/s²) A) 5550 J B) 6550 J C) 8150 J D) 13,100 J

Question

Quizplus · Accepted Answer

The gravitational potential energy at the top is mgh = 500 N * 50.0 m * sin(20°) = 1710 J. The work done by friction is 60.0 N * 50.0 m = 3000 J. The kinetic energy at the bottom is the initial potential energy minus the work done by friction: 1710 J - 3000 J = -1290 J. Since energy cannot be negative, the correct calculation should be: 500 N * 50.0 m * sin(20°) = 8550 J (potential energy), then subtract the work done by friction: 8550 J - 3000 J = 5550 J.

Preston Pushes a Wheelbarrow Weighing 500 N to the Top