Question

A circular loop of wire lies flat on a level table top in a region where the magnetic field vector points straight upward. The magnetic field suddenly vanishes. As viewed from above, in what direction does the induced current flow in the loop of wire?An induced current flows counterclockwise in the loop of wire.An induced current flows clockwise in the loop of wire.No current is induced in the loop of wire.The direction of the induced current cannot be determined from the given information.

Answer 1

Answer:

An induced current flow counterclockwise in the loop of wire

Explanation:

The magnetic field directed normally up wards and the magnetic flux directed upwards decreases suddenly.

The reduction in magnetic flux induces the EMF and current.

Magnetic field B points upward i.e. along she +z axis

B= z•k

Since the magnetic field vanishes, then, B=0

The force in field is given as

F=L( i×B)

For the magnetic field to vanish, the current has to move in opposite direction i.e. counterclockwise the loop wire.

Therefore the induced EMF and current will try to nullify this effect by producing more magnetic field directed up wards from the plane of the surface and this current have to flow in opposite or counterclockwise direction.