This question doesn't make a whole lot of sense. I am assuming you are dealing with a cylindrical polar orthonormal system, which is fine. But there is no such thing as finding "distances between vectors", because vectors do NOT have any position! All they have is direction and magnitude. That is why they can be picked up and moved anywhere you like.
#3
Drain Brain
143
0
maybe the problem is asking about a vector from A to B.
How can I do that?
#4
Evgeny.Makarov
Gold Member
MHB
2,434
4
You can convert cylindrical coordinates to Cartesian coordinates and use the standard formula for distance.
I'm reviewing Meirovitch's "Methods of Analytical Dynamics," and I don't understand the commutation of the derivative from r to dr:
$$
\mathbf{F} \cdot d\mathbf{r} = m \ddot{\mathbf{r}} \cdot d\mathbf{r} = m\mathbf{\dot{r}} \cdot d\mathbf{\dot{r}}
$$