Easy Conservation of Energy (Skiing)

AI Thread Summary
A skier descends from a height of 3500 m to 3400 m, covering a slope of 3000 m. The calculation for the skier's speed at the lower peak, using conservation of energy principles, yields a speed of 44.27 m/s. The length of the slope is deemed irrelevant since friction is neglected in the scenario. The discussion confirms the correctness of the calculation without needing to consider the slope length. Overall, the analysis aligns with the principles of energy conservation in this context.
TwinGemini14
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Two snow-covered peaks at elevations of 3500 m and 3400 m are separated by a valley. A ski-run having a total length of 3000 m extends from the top of the higher peak to the top of the lower one. A skier starts from rest on the higher peak. With what speed will the skier arrive at the topof the lower peak if she glides down the hill as fast as possible without any initial push? Neglect friction.

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h1 = 3500 m
h2 = 3400 m

mgh1 = 0.5mv^2 + mgh2
gh1 = 0.5v^2 + gh2

v = sqrt(2g(h1-h2))
v = 44.27 m/s
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Can anybody verify this with me? It looks good to me, but I did not use the information that the slope was 3000 m long. Is this unneccessary information or did I do something wrong?
 
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TwinGemini14 said:
It looks good to me, but I did not use the information that the slope was 3000 m long. Is this unneccessary information or did I do something wrong?

"Neglect friction."

That renders the length irrelevant.

Looks OK to me.
 
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