(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 50.0kg skier starts at A with an unknown initial velocity. The skier then goes over a hill (point B) which is 4.00m above point A. At point B (top of the hill), the skier experiences a Force normal 5/6 of his/her weight. The hill has a radius of 14.6m. What is the skier's initial velocity?

(Problem continues but only need help for this part)

2. Relevant equations

K=1/2mv^{2}

G=mgh

F_{c}=(mv^{2})/r

3. The attempt at a solution

So since the skier's "apparent weight" is 5/6 of his/her real weight, then force normal is = 5mg/6.

Since only gravity is holding the skier in a circle, then force centripetal = 5/6 force gravity.

([STRIKE]m[/STRIKE]v^{2})/r = (5/6)([STRIKE]m[/STRIKE]g)

v=sqrt(5/6)(9.81)(14.6)

v=10.92m/s

This is the speed of the skier at the top of the hill

Then we set the conservation of energy equation

K_{initial}= K_{hill}+ G

K = 1/2mv^{2}+ mgh = (0.5)(50.0)(10.92^{2}) + (50.0)(9.81)(4.00)

K = 2983.875J + 1962J = 4945.875J

1/2mv^{2}= 4945.875J

v= sqrt [(4945.875J)(2)/(50.0kg)]

v=14.07m/s

It seems logical to me but for some reason it is not correct : /

Help appreciated thanks :)

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# Homework Help: What is the skier's initial velocity?

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