Question

A 0.30 radius automobile tire accelerates from rest to a constant 2.0 rad/s. what is the centripetal acceleration of the point on the outer edge of the tire after 5.0seconds?

i have no clue where to begin on this one can anyone help? do i leave the 2.0 inrad/s or convert to m/s.

(0.30m)(2.0^2)/5s =33.0 m/s^2 is this right?

Answer 1

Your acceleration rate should be written in units of rad/s^2, not rad/s. You should also give the units of the radius R, which I assume is meters.

After 5 s the angular velocity of the tire is
w = 5 x 2 = 10 rad/s, if I am interpreting the problem correctly. I think they are giving you the angular acceleration rate, not the final angular velocity at the end of 5 seconds.

Centripetal acceleration is equal to R w^2

Answer 2

25 radians!