Question Detail
Question
For a rectangular loop of depth D moving with velocity v perpendicular to a uniform magnetic field B (where B, D, and v are perpendicular to each other), what is the magnitude of the motional EMF generated, assuming the loop is either entering or leaving the field?
Correct Answer
Option B is the correct answer.
Detailed Explanation
Slide 21 shows the derivation: The flux is ΦB = BDx. The rate of change of flux is dΦB/dt = BDdx/dt. Since dx/dt represents the velocity v (or -v), the magnitude of dΦB/dt is BDv. From Faraday's Law, E = -dΦB/dt, so the magnitude of the EMF is BDv.
Hint
Recall the formula for magnetic flux (B times Area) and how it changes with respect to time when a conductor moves in a magnetic field.