Finding friction from tangential acceleration

[pcandrepair]

[SOLVED] Finding friction from tangential acceleration

Homework Statement

A car traveling on a flat (unbanked) circular track accelerates uniformly from rest with a tangential acceleration of 2.25 m/s^2. The car makes it one quarter of the way around the circle before it skids off the track. Determine the coefficient of static friction between the car and track from these data.

Homework Equations

$$\theta$$final = 90
$$\theta$$initial = 0

friction = mass(net acceleration)

$$\mu$$ = (sqrt((tan accel.)^2) + ((radial accel.)^2))) / g

The Attempt at a Solution

I know the above equation is used to find the coefficient of friction but I do know how to find the radial acceleration from what is given. Any help would be greatly appreciated. Thanks.

 

[pcandrepair]

Nevermind...I figured it out.