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

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To determine the work required to pull a 70 kg skier up a 60 m slope at a 30-degree angle, the relevant equation is W = F (delta)r cos(theta). The force acting on the skier should be calculated using the gravitational potential energy concept rather than the initial approach, which incorrectly uses Joules for force. The correct force can be derived from the skier's weight and the slope's angle. The discussion emphasizes that considering gravitational potential energy simplifies the calculation. Accurate understanding of units and forces is crucial for solving the problem effectively.
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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?
 
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scurry18 said:

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:
scurry18 said:
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.
 

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