How Much Work Does It Take to Pull a Skier Up a Slope?

[scurry18]

Homework Statement

A skier of mass 70.0 kg is pulled up a slope by a motor-driven cable.
How much work is required to pull the skiera distance of 60.0m up a 30 degree slope (assumed frictionless) at a constant speed of 2.00 m/s?

Homework Equations

W=F (delta)r cos(theta)

The Attempt at a Solution

(delta)r= 60.0m
(theta)=30.0 degrees
Force=60sin30=30 J


Is this the correct start?

 

[Hootenanny]

Homework Statement

A skier of mass 70.0 kg is pulled up a slope by a motor-driven cable.
How much work is required to pull the skiera distance of 60.0m up a 30 degree slope (assumed frictionless) at a constant speed of 2.00 m/s?

Homework Equations

W=F (delta)r cos(theta)

The Attempt at a Solution

(delta)r= 60.0m
(theta)=30.0 degrees

It's all good up until this point:

Force=60sin30=30 J

Firstly force is measured in Newton's and not Joule's. Secondly, how did you calculate the force acting on the skier?

HINT: This problem is much more straight forward if one simply considered the gravitational potential energy of the skier.