# Magnetic field

1. Sep 12, 2009

### howt

1. The problem statement, all variables and given/known data
http://img3.imageshack.us/img3/2178/9b26f2dd8dd8a8686c9c8c2.th.png [Broken]

2. Relevant equations

$\vec{\upsilon}= \vec{\Delta} V / ( B d)$

$\vec{\upsilon}= u E$

3. The attempt at a solution

from the diagram , we have $\vec{\upsilon} = 1.25*10^-5 V/(B)(0.001m)$

using the second formula ( 1.25*10^-5 )V/(B)(0.001m) = 3.5*10^-5 (240V)(0.12m)

in which I got B = 1.7857*10^-7, which is wrong...
why?

Last edited by a moderator: May 4, 2017
2. Sep 15, 2009

### tiny-tim

Last edited by a moderator: May 4, 2017
3. Sep 16, 2009

### howt

Thank you very much for info, I was wondering why no1 bother to reply...
The link somehow manage to show a picture on my computer.

Well, the question have been solved by my friend. It is no longer a problem.
Thank you again for telling me though