Electric and Magnetic field relationship

AI Thread Summary
The discussion revolves around proving the relationship B = k(v × E), where B represents the magnetic field, v is velocity, and E is the electric field. Participants express confusion about the origin of this equation and whether it applies generally or in specific scenarios. There is a focus on starting points for the proof, including the fundamental equations F = qE and F = q(v × B). The need to determine the units of k and explore vector relationships between E and B is also highlighted. Overall, the conversation seeks clarity on how to approach the proof of this electromagnetic relationship.
Tareth
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Homework Statement


Show that B = (k)v(cross)E


The Attempt at a Solution


I have no idea where to start. I have the F = qE and F = q(v(cross)B)
 
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Just a starting point would be much help.
 
Tareth said:
Just a starting point would be much help.

did you post the question exactly?

Is the question asking to prove that in general:

B = k\vec{v}\times\vec{E}

I don't recognize this relationship... is this for a specific situation?
 
That is the first part of the problem.

Show that \vec{B} = k\vec{v}\times\vec{E}

Find the fundamental units of k, which I believe I have correct as m^2/s^2

Find \vec{B}(dot)\vec{E}

Find \vec{E}\times\vec{B}

I believe with the 1st part I can figure the rest out. I just don't know where to start to prove the first part.
 
Tareth said:
That is the first part of the problem.

Show that \vec{B} = k\vec{v}\times\vec{E}

In general? Or for a specific situation?
 
In general.
 
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