Question

Two coils have a mutual inductance 0.005H. The current changes in a coil according to equation I = I_o sin ωt. Where I_o = 10 A & ω = 100 π rad s^–1. The maximum value of emf in second coil is ………… 

(a) 2π 

(b) 5π 

(c) π 

(d) 4π

Answer 1

The correct option (b) 5π

Explanation:

M = 0.005H, I = I_o sinωt

e = M ∙ (dI/dt)

= M (d/dt) (I_o sinωt)

= M I_o cos ωt(ω)

e= M I_o ω cosωt

e_max = M I_o ω(1) = M I_oω

∴ e_max = 0.005 × 10 × 100 π = 5 π.