A current of 15A in the primary coil of a circuit is reduced to zero at a uniform rate in $10^{-6}s$. If the coefficient of the Mutual Inductance is 4 H, what is the Induced emf in the secondary coil?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $6×10^7 V$
The induced electromagnetic force (emf) of the secondary coil is,
$ε_2=-M\frac{dI_1}{dt}$
and,
$\frac{dI_1}{dt}=\frac{ΔI_1}{Δt}=\frac{15A}{10^{-6}s}=1.5×10^7A/s$
∴ Induced emf, $ε_2=-(4H)×(1.5×10^7A/s)$
$=-6×10^7 V$