Calculating Work: Solving a Skiing Problem on a 30 Degree Slope

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To calculate the work required to pull a skier up an 80-meter slope at a constant speed of 3.1 m/s on a 30-degree incline, the formula W = (Fcos(theta)) * delta x is used. The skier's mass is 64 kg, leading to a force calculation that includes gravitational components. The initial calculation yielded 13745.6 joules, but the user later confirmed they resolved their confusion. The discussion highlights the importance of correctly applying trigonometric functions in work calculations on slopes. The final work required for the trip is clarified through the user's realization of their earlier miscalculation.
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A skier of mass 64 kg is pulled up a slope by a motor-driven cable. How much work is required to pull him 80 meters up a 30 degree slope (assumed frictionless) at a constant speed of 3.1 meters/second? [answer is to be in joules]


Ok, so the equation I am using is W = (Fcos(theta))*delta x

I tried using the values above and I've done it over and over and still came up with the same number.

W = ((3.1*64)*cos30)*80

= 13745.6

Am I missing something obvious? Thanks in advance for any helpful suggestions.
 
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If there was no slope, a force of what magnitude would be required to keep up a constant speed?
And as dW = F dx, how much work would be required for the 80m trip?

Hope this helps you figure out what you did wrong :).
 
Last edited:
Ok, I got it . . .Thank you.
 
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