Question

a metal strip 6.5cm long,0.88cm wide &0.76mm thick moves with constant velocity v through a magnetic field B=1.2mT perpendicular to the strip.A Potential difference of 3.9V is measured between points x & y across the strip.Calculate the speed V.

Answer 1

When the conductor is moving in the magnetic field perpendicular to the field the generated motional electromotive force will generate the voltage equal to

$$emf=vBl$$

where l is a length of the wire in the direction perpendicular to the speed vector.

Out of this equation we can calculate the speed v to be equal to

$$v=emf/Bl=3.9/(0.065∗1.2∗10^{−3})=50000m/s$$