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

Hey guy's im kind of struggling with this i would appreciate any help

A potter's wheel having a radius 0.49 m and a moment of inertia of 12.1 kg · m2 is rotating freely at 52 rev/min. The potter can stop the wheel in 6.0 s by pressing a wet rag against the rim and exerting a radially inward force of 74 N. Find the effective coefficient of kinetic friction between the wheel and the wet rag.

2. Relevant equations

kinematics

Wnc = ΔRotational Energy

3. The attempt at a solution

Ok here so i started this one trying to do an energy conservation 74Δx(or θ) + uknΔx = (1/2)iω^2

To represent the non conservative forces on one side and the change in rotational kinetic energy on the other, Δx being the stopping distance that can be obtained from kinematics

then i figured there might be a radial component instead of a torque

ƩFr = n + 74 = v^2/r*m

so the radial component gives u an n i can sub back in the conservation equation and it points in the same direction, is this anywhere near right or should i be representing the forces over a torque

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# Homework Help: Introductory rotational dynamics/energy conservation question

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