How to Calculate Work at a 30 Degree Angle on a Ski Slope?

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To calculate the work required to pull a skier up a 30° slope, one must consider the forces acting on the skier, including gravitational force and the slope's angle. The work done can be expressed as W = Fcos(θ)Δr, where F is the force exerted by the cable and Δr is the distance moved. Understanding that the skier's weight can be resolved into components parallel and perpendicular to the slope is crucial for determining the force needed to counteract gravity. The skier's mass (71 kg) and the distance (55 m) can be used to calculate the gravitational force, and since the skier is moving at a constant speed, the net force is zero, simplifying the calculations. Clarifying the use of vectors and the relationship between force and distance is essential for solving this problem effectively.
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A skier of mass 71 kg is pulled up a slope by a motor-driven cable.
(a) How much work is required to pull him a distance of 55 m up a 30° slope at a constant speed of 1.1 m/s

My whole problem with this question is that I'm not sure if I need to include ∑Fx and ∑Fy (where ∑Fx = mgsinӨ=ma and ∑Fy= n-mgcosӨ) in order to find F. This is where I'm getting stuck to solve for W
W=FcosӨ Δr
I just need help in getting started with this problem because I keep getting stuck. Any help would be greatly appreciated.
 
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I think you can just use the simple W = F \times d equation for this problem. The total distance can be calculated using trigonometry.
You know that F = m \times a \ \Longrightarrow \ F = m \times \frac{d}{t^2}.
And you can also calculate the total time it takes to move the object to the final destination since you know the distance and the velocity of it. I think this would work.
 
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W = mg = 71 kg * 9.8 m/s2.

However, the Weight points directly down with gravity. Weight (force) is a vector, and it can be resolved into two components, one normal to the slope surface, and one parallel, pointing down hill. The cable would be pulling up hill at constant speed. Constant speed means not acceleration so no net force.
 
I'm still confused as to what you are describing. Plus I figured vectors were involved however my book doesn't really explain how to use vectors in relation to this sort of problem. Could you explain a little more any help is appreciated.
 
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