Question

How is motional emf induced?

Answer 1

Let's say you have a metal rod, and decide to connect that to your galvanometer. If the rod is stationary in a magnetic field, nothing happens. If you move the rod through the field, however, an emf is induced between the ends of the rod causing current to flow. This is because when you move the metal rod through the field, you are moving all the electrons in the rod. These moving charges are deflected by the field toward one end of the rod, creating a potential difference. This is known as motional emf.