# Formula Circular Motion Centripetal acceleration    Velocity    Radius

## Centripetal acceleration

Unit
It is the acceleration experienced by a body (e.g. a planet, a particle) moving on a circular path. The centripetal acceleration points like the centripetal force to the center of the circle (in radial direction).

The centripetal acceleration is larger, the larger the velocity $$v$$ of the body and the smaller the radius $$r$$ of the circular orbit.

For example, if a body with $$v = 2 \, \frac{\mathrm m}{\mathrm s}$$ moves on a circular orbit with radius $$r = 1 \, \mathrm{m}$$, then this body experiences the following centripetal acceleration:\begin{align} a_{ \text z } &~=~ \frac{(2 \, \frac{\mathrm m}{\mathrm s})^2}{ 1 \, \mathrm{m} } \\\\ &~=~ 4 \, \frac{\mathrm m}{\mathrm{s}^2} \end{align}

## Velocity

Unit
Velocity of the body moving in a circle.