Question

A 60 kg skier starts from rest at ground level. She uses her poles to push herself up a hill that is 6 m high. If her final speed is 3 m/s, find the work she does.

A) 1800 J
B) 900 J
C) 3600 J
D) 600 J

Answer 1

The work done by the skier is 1800 J.

Step-by-step explanation:

To find the work done by the skier, we can use the work-energy theorem, which states that the work done on an object is equal to the change in its kinetic energy. In this case, the skier starts from rest and reaches a final speed of 3 m/s, so the change in kinetic energy is:

ΔKE = (1/2)mv^2 - (1/2)m(0)^2 = (1/2)m(3^2)

Since the problem only asks for the work done, we can simply multiply the change in kinetic energy by the mass of the skier:

Work = ΔKE = (1/2)(60 kg)(3 m/s)^2 = 1800 J

Therefore, the work done by the skier is 1800 J (option A).