Question

If the emf produced in a wire is 0.88 volts and the wire moves perpendicular to a magnetic field of strength 0.075 newtons/amperes•meter at a speed of 4.20 m/s what is the length of the wire in the magnetic field?
A.) 0.27m
B.) 2.8m
C.)0.020m
D.) 3.7m

Answer 1

there is a nifty equation for the EMF \( \mathcal{E} \) generated in a wire length \(l\) moving perpndicularly to a B field at constant velocity \(v\):

\( \mathcal{E} = Blv\)

There is a very followable explanation here:
http://www.solitaryroad.com/c1048.html

And probably loads more over the web.


with \(l = \dfrac{ \mathcal{E} }{B v}\), .... wonder what the answer might B ?!