Question

A square loop of side length $a$ having $n$ turns is kept in a horizontal plane. A uniform magnetic field $B$ exists in vertical direction as shown in figure. Now, the loop is rotated with constant angular speed $\omega$ as shown below.
Which of the following statement is correct?

• A. Same emf is induced in both cases (i) and (ii)
• B. Maximum emf is induced in case (i)
• C. Emf induced in case (ii) is more than (i)
• D. No emf induced in case (ii)

Answer 1

The correct option is C Emf induced in case (ii) is more than (i)

In the configuration (i), the coil rotates in horizontal plane about an axis passing through the centre and perpendicular to plane of the coil. During this movement of the coil, magnetic flux associated with the coil remains constant. Hence, emf induced is zero.
In the configuration (ii), magnetic flux associated with the coil changes sinusoidally and hence the emf is induced.