Splung.com Physics Forum

[ptejav]

A particle moves with a constant angular acceleration Alpha in a circular path. The time at which the magnitude of tangential and radial accelerations are equal is
a) 1/Alpha b) Sq.root Alpha c) 1/Sq.root Alpha d) Alpha

Please explain[/code][/list]

[hepcj]

I would use dimensional analysis. You want the answer to come out in seconds and you know that the angular acceleration is measured in rad s^-2. (radians don't have a dimensional unit as they are a measurement of angle.)