Calculating Friction Force on a Rotating Disk

AI Thread Summary
The discussion revolves around calculating the friction force on a rotating disk, where the friction increases as the rotary frequency doubles. The user attempts to relate the friction force to the angular frequency but is uncertain about their calculations. It is suggested that the only horizontal force acting is friction, which can be determined using the formula F = ma. The conversation emphasizes the need to find the acceleration at the given angular frequency to solve for the friction force accurately. Understanding these relationships is crucial for correctly determining the friction force at the original frequency.
5Mystery
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Homework Statement



The thing that is lying on the disk(Disko), is rotating together with disko. After the rotary frequency of disko grew twice (N X 2), friction(rubbing) Force grew F=6 ( F + 6). You have to understand friction Force module at the original frequency.


Homework Equations



I don't know. Probably, 2N = F + 6 : m X g

The Attempt at a Solution



2N = F6 : mg = F6 : 9,8
F = 9,8 : 6

but I don't think it is correct please help me. Sorry if there are some mistakes but I really need it please do not delete this post.
Thank you very much. :)
 
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Welcome to PF!

Hi 5Mystery! Welcome to PF! :smile:

The only horizontal force is the friction (and the only motion is horizontal).

So you can find the friction, F, by using F = ma.

So what is the acceleration (a), at an angular frequency ω? :wink:
 
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