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

A 1.2 g pebble is stuck in a tread of a .76-m-diameter automobile tire, held in place by static friction that can be at most 3.6 N. The car starts from rest and gradually accelerates on a straight road. How fast is the car moving when the pebble flies out of the tire tread?

2. Relevant equations

alpha=net Torque/I=FR/MR^2

so: (3.6)(.38)/(.0012)(.38^2)=7895 rad/s^2

now my plan is to use s=R * theta to find theta (where s is the distance the pebble travels along the circular pathway), plug that value into wf^2=wi^2 + 2alpha * theta and then use the value I get for Wf in equation v=wr to get v. but the problem is I don't know how to find s because I don't know what distance the pebble travels along the circular pathway. Can someone please help? Thank you :)

3. The attempt at a solution

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# Homework Help: How fast is car moving when . . .

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