Question

If a wire is dropped freely towards Earth will an EMF induced across the ends of wire if the wire is initially in (a) north south direction ,(b) east west direction ?

Answer 1

The magnitude of induced emf in a circuit is equal to the rate of change of magnetic flux linked with it. E=∣∣dϕdt∣∣ Condition for maximum flux linked to the surface: Plane of the surface is perpendicular to the magnetic field Condition for minimum flux linked to the surface: Plane of the surface is parallel to the magnetic field Case I:(wire pointing north-south) Here, the the ends of the wire are pointed towards the magnetic field of Earth, which is in north-south direction. Hence, minimum flux is linked to the surface andno emf is induced in the wire. Case II:(wire pointing East-West) Here, the ends of the wire are pointed in perpendicular to the magnetic field of Earth, which is in north-south direction. Hence, maximum flux is linked to the surface andemf is induced in the wire