Centripetal Acceleration and Tangential Acceleration problem driving me crazy

[roflawlz]

A car is tested on a 230 m diameter track.
If the car speeds up at a steady 1.2 m/s^2, how long after starting is the magnitude of its centripetal acceleration equal to the tangential acceleration?

it seems simple, but i just can't seem to get it!...
find: change in time when centripetal acceleration = tangential acceleration.
r = 115 m.
a = 1.2 m/s^2 (which type of a, i don't know)
centripetal accel = v^2/r or w^2/r
tangential accel = (radius)(angular accel)

i tried setting them equal to each other obviously, but no luck. can someone help me out??

 

[spork]

>> centripetal accel = v^2/r or w^2/r

centripetal accel = v^/r NOT w^2/r


>> tangential accel = (radius)(angular accel)

Nope, tangential accel is simply the acceleration given in the problem statement - 1.2 m/s^2

What speed must the car be going to give it a centripetal acceleration equal to 1.2 m/s^2 ? How long will it take to reach this speed?

Make sense?