A 60-kg skier starts from rest from the top of a 50-m high slope.If the work done by friction is -6.0 kJ,what is the speed of the skier on reaching the bottom of the slope?
A)17 m/s
B)24 m/s
C)28 m/s
D)31 m/s

Question

Quizplus · Accepted Answer

Work done by gravity = mgh = 60 kg * 9.8 m/s^2 * 50 m = 29.4 kJWork done by friction = -6.0 kJNet work done = 29.4 kJ - 6.0 kJ = 23.4 kJKinetic energy of the skier at the bottom of the slope = 23.4 kJSpeed of the skier = sqrt(2 * 23.4 kJ / 60 kg) = 28 m/s

A 60-Kg Skier Starts from Rest from the Top of a 50-M