- #1

ed2288

- 25

- 0

I know that for an infinitely long current carrying wire, the magnitude of the magnetic field is given by (mu_0*I)/(2*Pi*R) where mu_0 is the magnetic permeability of free space.

What I would like to know is what is the vector form of this equation? i.e. How can you determine which way the B-field points? I've looked all over the internet but can't find anything! Does there need to be a cross product with r-hat in there somewhere!