Question

The mutual inductance between two coils is 2.5 H. If the current in one coil is changed at the rate of 1 As⁻¹, what will be the emf induced in the other coil?

Answer 1

Given:
Mutual inductance between the coils, M = 2.5 H
Rate of change of current in one coil, $\frac{di}{dt}$ = 1 As⁻¹
The flux in the coil due do another coil carrying current i is given by
ϕ = Mi
The emf induced in the second coil due to change in the current in the first coil is given by
$$\begin{gathered} e=\frac{d\varphi }{dt} \\ \Rightarrow e=\frac{d\left(Mi\right)}{dt}=M\frac{di}{dt} \\ \Rightarrow e=2.5\times 1=2.5\mathrm{V} \end{gathered}$$