Thread: a coin in a funnel View Single Post

## a coin in a funnel

1. The problem statement, all variables and given/known data
A coin(radius=r) rolls in a funnel only with a horizontal speed v. The coin always stays at his altitude.
The coin has a homogen mass distribution and it only rolls! So it has a translational motion and a rotation motion.
Find a function R(z) whitch discribes the form of the funnel!
R>>r and z is the altitude of the funnel. the z-coordinate of the coin is changeless.

2. Relevant equations

I thougth it must be $$\tan\alpha=\frac{v^2}{r\cdot g}$$

But then i tought the speed at all parts of the coin isnt the same.

If there are any questions in understand my problem, ask!
I made a drawing of that:

Can u pls help me?
Thank you
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution
Attached Thumbnails

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