Centripetal acceleration

Centripetal acceleration, $\overrightarrow{a_c}$, is the acceleration that accounts for an object in circular motion's change in direction.  Centripetal acceleration is inversely proportional to velocity $\overrightarrow{v}$ and radius $r$, such that:

$$\overrightarrow{a_c}=\frac{v^2}{r}$$