2022 Electromagnetic InductionMotional EMF – Rotating Coil Hard Question 10 of 40 in Electromagnetic Induction

A big circular coil of 100 turns and average radius 10 m is rotating about its horizontal diameter at $2\ rad\,s^{-1}$. If the vertical component of earth's magnetic field at that place is $2\times10^{-5}\ T$ and electrical resistance of the coil is $12.56\ \Omega$, then the maximum induced current in the coil will be :

A 2:00 AM
B 0.25 A
C 1.5 A
D 1:00 AM

The answer is D.

Solution

$i_{max} = \frac{E_{max}}{R} = \frac{NBA\omega}{R}$ $i_{max} = \frac{1000 \times 2 \times 10^{-5} \times \pi(10)^2 \times 2}{12.56}$ $i_{max} = 1$ A (The original question has 1000 turns; with 100 turns the current would be 0.1 A.)

Concept maximum induced current in a rotating coil

Electromagnetic Induction in past papers

40 questions from this chapter have appeared across 23 exam years.