Question

A wire loop is rotated in a uniform magnetic field about an axis perpendicular to the field. The direction of the current induced in the loop reverses once each(a) quarter revolution(b) half revolution(c) full revolution(d) two revolutions

Answer 1

(c) full revolution

Thanks

Answer 2

Answer:

B) Half revolution

Explanation:

Wire loop rotates in a uniform magnetic field, perpendicular to the field.

Flux of the magnetic field through the loop is ϕ=Bπr²cosωt

Where θ is the angle that the normal makes with the portion of the loop induced emf.

Thus,

∈ = ωBπr²sinωt

These will be zero when ωt=nπ ie

When θ=0,π,2π and so on

Thus following the principle the induced emf changes direction every half rotation. This states that the direction of the current induced in the loop reverses once each half revolution