- #1

Femme_physics

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## Homework Statement

http://img39.imageshack.us/img39/3778/funkyrider.jpg

So I got this funky rider that starts its movement from the top of the hill A at initial speed (Vo). From that point, the bicycles role on freely (without using pedals) at the circular path.

Calculate the velocity of the rider at the bottom point B.

W= (weight of the rider+bicycle) = 650 [N]

Vo (initial velocity) = 27 km/h

H = 14m

R= 10m

Comment: Ignore friction

C is point mass

## The Attempt at a Solution

HERE is my problem. Last year in my notebook I wrote this:

http://img204.imageshack.us/img204/6220/vfold.jpg

I tried resolving it but I didn't get the same result. This result is the same one in the manual so I reckon it's correct.

I tried

a = -9.81

a = 9.81

a = v

^{2}/R = 7.5

^{2}/10

a = g

^{2}/R = 9.81

^{2}/2

Nothing works. The third one makes slight sense to me because according to the formula of circular motion that's what "a" ought to be, v

^{2}/R...problem is that using this I'm not considering "g" and that's impossible, therefor the last a makes most sense to me. None of them gives me my old answer!

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