1. The problem statement, all variables and given/known data A 1.2 g pebble is stuck in a tread of a 0.76 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? I know the answer is 17 m/s however I don't know how to get it. 2. Relevant equations v=(2*[itex]\pi[/itex]*R)/T v=ωR [itex]\alpha[/itex]=τ/I I=1/2*M*R2 Fc=(m*v2)/2 3. The attempt at a solution I tried using the centripetal force equation and rearranged for velocity, using the maximum static friction as my force. I then divided that number by 2 to get the speed in the centre of the wheel (since the speed at the top of the wheel is twice the speed of the vehicle).