A disc of radius 0.1 m is rotating with a frequency 10 rev/sec in a normal magnetic field of strength 0.1 tesla. Net induced emf is

Options

(a) 2 π x 10⁻² V
(b) 4 π x 10⁻² V
(c) π x 10⁻² V
(d) 3 π x 10⁻² V

Correct Answer:

π x 10⁻² V

Explanation:

Induced emf = Baʋ

= 0.1 × π (0.1)² × 10

= 0.1 × 0.1π × 10

= π × 10⁻³ × 10

= π × 10⁻² V