Power Needed to Pull Skier Up Slope

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To determine the power required to pull a skier up a slope, the skier's mass, slope angle, speed, and coefficient of kinetic friction are key factors. The net force acting on the skier is zero due to constant velocity, leading to the equation T = F|| - Ff, where T is tension, F|| is the parallel component of gravitational force, and Ff is the force of friction. Calculating the force of friction involves finding the normal force, which is the weight component perpendicular to the slope. Clarification is needed on the direction of the forces involved; the parallel gravitational force and friction act in opposite directions to the tension in the cable. Accurate calculations are essential for determining the correct power output from the motor.
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Homework Statement


A skier of mass 78.7 kg is pulled by a motor-driven cable up a 31.9 ° slope at a constant speed of 1.04 m/s. If the coefficient of kinetic friction between the skis and the slope is 0.270, what power must be delivered by the motor pulling the cable?

Homework Equations



P=FV

The Attempt at a Solution


The Fnet of the skier will be 0 because the velocity is constant.
To find the F|| of the skier I used the equation mgsin(x) and umg to find Force friction(Ff)
Therefore, T=F||-Ff
and therefore P=T*v
but everytime I do this I get the wrong answer, and I don't know why??Please help!
 
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To find the force of friction, you need the normal force, which is balancing w_perpendicular (mg cos x). Force of friction is mu times this normal force.

And also, are w_parallel and friction in the same direction as each other, or opposite? Is just one of these forces or both of them pointing opposite of tension?
 
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