Question

A current i, indicated by the crosses in figure, is established in a strip of copper of height h and width w. A uniform field of magnetic induction B is applied at right angle to the strip. Calculate voltage V necessary between two sides of the conductor in order to create this field E. Between which sides of the conductor would this voltage have to be applied?

• A. $5\times {10}^{-6}$ Top and Bottom, with top +ve charge and bottom -ve charge
• B. $5\times {10}^{-6}$ Top and Bottom, with top -ve charge and bottom +ve charge
• C. $5\times {10}^{-6}$ Any
• D. None of the above

Answer 1

The correct option is A $5\times {10}^{-6}$ Top and Bottom, with top +ve charge and bottom -ve charge

Necessary voltage to produce this field is:
$V=E\times h=(2.8\times {10}^{-4})\left(0.02\right)=5.6\times {10}^{-6}V$.
This voltage should be applied between top and bottom sides with top voltage positive and bottom negative.