A wire is kept along:
(a) north-south direction
(b) east west direction
when the wire is allowed to fall freely, will there be induced emf set up in the wire? Justify your answer giving reasons for both the above mentioned cases

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 and no 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 and emf is induced in the wire.

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