The formula for centripetal acceleration, a, is given below, where v is the velocity of the object and r is the object's distance from the center of the circular path.
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This is the same as writing v = sqrt(ar)
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Work Shown:
[tex]a = \frac{v^2}{r}\\\\ar = v^2\\\\v^2 = ar\\\\v = \sqrt{ar}\\\\[/tex]
I multiplied both sides by r to isolate the v^2 term, then I applied the square root to fully isolate v.