The formula for converting a linear velocity expressed in $m.s^{-1}$ into an angular velocity expressed in $rad.s^{-1}$ is given by :

$$\omega = \frac{v}{r}$$

With :

• $\omega$ angular velocity expressed in $rad.s^{-1}$
• $v$ linear velocity expressed in $m.s^{-1}$
• $r$ radius, expressed in $m$

For example, if a vehicle with wheels of radius 10 cm move at a speed of 2 m/s, the angular velocity of the wheels is given by :

$$\omega = \frac{v}{r} = \frac{2 \text{ m/s}}{0.1 \text{ m}} = 20~ rad.s^{-1}$$

You'll find on this page an online converter from linear to angular velocity.