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**shilz222** A particle moves in a plane with constant radial velocity $\displaystyle \dot{r} = 4 \ \frac{m}{s} $. The angular velocity is constant and has magnitude $\displaystyle \dot{\theta} = 2 \ \frac{rad}{s} $. When the particle is $\displaystyle 3 \ m $ from the origin, find the magnitude of (a) the velocity and (b) the acceleration.

So $\displaystyle \bold{v} = v_{r} \bold{\hat{r}} + v_{\theta} \bold{\hat{\theta}} $ where the first component is the radial velocity and the second component is the angular velocity.

So we want units in $\displaystyle \frac{m}{s} $ (same units). So would I just change the $\displaystyle 2 \ \frac{rad}{s} $ into $\displaystyle \frac{m}{s} $ and take the magnitude?

If we have constant velocity (both radial and angular) wouldn't the magnitude of the acceleration be $\displaystyle 0 $?