What I'm doing seems like it should work, but I can't seem to get it right. I'm sure I'm doing the math right, but I have a feeling I'm answering something that's not being asked. I would just like some help on setting up the equation right.(adsbygoogle = window.adsbygoogle || []).push({});

A car starts from rest on a flat circular track of radius 200.1 m and accelerates tangentially at a rate of 4.79 m/s^{2}. How much time elapses before the centripetal acceleration of the car is equal in magnitude to the tangential acceleration.

I have the tangential acceleration (a_{t}), and radius (r).

Using the centripetal acceleration equation a_{c}=v^{2}/r, I set a_{c}=4.79 m/s^{2}, r=200.1m, and solve for the velocity.

I then use the circular motion period equation (v=(2*pi*r)/t), plug in the velocity I just calculated, the radius of the track, and solve for time.

I get 40.61s everytime, which is incorrect.

vv I got it now. Thanks for saving my hair.

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# Circular motion

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