Question

When a current of $4A$ between two coils changes to $12A$ in $0.5s$ in primary and induces an emf of $50mV$ in the secondary. Calculate the induced emf in the secondary if current in the primary changes from $3A$ to $9A$ is $0.02s$

Answer 1

$M=\frac{e_2}{d{i}_2/dt}=\frac{(50\times {10}^{-3})}{\left(8/0.5\right)}$

$=3.125\times {10}^{-3}H=3.125mH$

$e_1=M\left(\frac{\Delta i_2}{\Delta t}\right)$
= $\frac{(3.125\times {10}^{-3})\left(6\right)}{0.02}=0.9375V$