Calculating Angle and Height in Conservation of Energy Problem with Friction

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The discussion revolves around calculating the angle θ of a slope using the law of conservation of energy for a skier sliding down while experiencing friction. The skier's mass is 46 kg, and the slope length is 21.7 m, with a kinetic friction force of 41 N. Initial and final speeds are given as 0.65 m/s and 7.19 m/s, respectively. The participant initially struggled to find the height without knowing the angle but later determined the height using energy conservation and calculated the angle to be approximately 12 degrees. The approach taken involved isolating sin θ from the energy conservation equation and applying trigonometric functions to find the angle.
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Homework Statement


A 46 kg skier slides down a slope 21.7 m long, incilned at an angle θ to the horizontal. The magnitude of the kinetic friction force is 41 N. The skier s initial speed is 0.65 m/s and the speed at the bottom of the slope is 7.19 m/s. determine the angle θ from the law of conservation of enegery. Air resistance is neglible


Homework Equations



PE=mgy, KE= 1/2mv^2, W=F*d, Ff=μmgsinθ

The Attempt at a Solution


My attemp at the equation was based on the law of conservation of energy with this resulting formula

(mgh+1/2mv^2-mgh-1/2mv^2)/Ff*d=sinθ

I can't figure out how to find the height without an angle or vice versa, i ve been trying to figure it out for the last little bit with no success. I feel like I m missing just one step
 
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TheMasterFool said:

Homework Statement


A 46 kg skier slides down a slope 21.7 m long, incilned at an angle θ to the horizontal. The magnitude of the kinetic friction force is 41 N. The skier s initial speed is 0.65 m/s and the speed at the bottom of the slope is 7.19 m/s. determine the angle θ from the law of conservation of enegery. Air resistance is neglible


Homework Equations



PE=mgy, KE= 1/2mv^2, W=F*d, Ff=μmgsinθ

The Attempt at a Solution


My attemp at the equation was based on the law of conservation of energy with this resulting formula

(mgh+1/2mv^2-mgh-1/2mv^2)/Ff*d=sinθ

I can't figure out how to find the height without an angle or vice versa, i ve been trying to figure it out for the last little bit with no success. I feel like I m missing just one step


How much work was done against friction during the slide?
 
Hey I think i figured it out, I took sin theta outta my energy conservation since it gave me the resisting force of 41N. I then used the energy conservation formula to find height and then O/H sin -1 to find my angle which turned out to be sig fig 12 degrees. It feels right but I guess I ll find out and post again.
 
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