Impulse and angular velocity I haven't really well understood the interrelation between impulse and angular velocity in the dynamics of rigid bodies. For instance let's suppose we have a bar that is placed vertically on a frictionless surface. If we apply a certain impulse at a certain distance to the bar, how can we determine the angular velocity of the bar thereafter?
 A: To understand how impulse and angular velocity are related, we need to distinguish between linear and rotational quantities. Impulse relates to the change in linear momentum, $\mathbf{p}$, over time (as opposed to angular momentum $\mathbf{L}$). 
$$\mathbf{J} =\frac{d \mathbf{p}}{dt}$$
To relate the two, we need the relationships between linear and rotational, which is done via cross products or dot products:
$$ \mathbf{L} = \mathbf{r}\times \mathbf{p}$$
$$ \mathbf{v} = \mathbf{\omega} \times \mathbf{r} $$
$$etc$$
Also, you will need to define a pivot point around which the object rotates. The logical choice is the point of contact with the floor. 
If you know the impulse given to the rod, and want to know $\omega$, note that torque is $\mathbf \tau =\frac{d\mathbf L}{dt} =\frac{d}{dt}(\mathbf r\times \mathbf p) = \frac{d\mathbf r}{dt}\times \mathbf p + \mathbf r\times \frac{d\mathbf p}{dt}$. If we apply the impulse quickly to the rod, so that it is always at a constant distance $r$ from the pivot point, $\frac{d\mathbf r}{dt} = 0$ and so we have just $\mathbf \tau = \frac{d\mathbf L}{dt} =\mathbf r\times \frac{d\mathbf p}{dt}$. We know then that $\mathbf \tau = \frac{d\mathbf L}{dt} =\mathbf r\times \mathbf J$. So, we have related our linear quantity $\mathbf J$ to the angular quantity $\mathbf \tau$. Lastly, we know that $\mathbf \tau = I\mathbf \omega$, so that $\mathbf r\times \mathbf J = I\mathbf \omega$. This will relate the two quantities for your problem.
A: If you apply an impulse to a bar at a certain point on a frictionless surface($\mu=0$), then the bar will not rotate but will translate. For the existence of rotation, you require a coupled force, not a linear impulse
