S L Arora Solutions for Chapter: Electromagnetic Induction, Exercise 1: Problems For Practice

Calculate the mutual inductance between two coils when a current of $2 \mathrm{A}$ changes to $6 \mathrm{A}$ in $2 \mathrm{s}$ and induces an emf of $20 \mathrm{mV}$ in the secondary coil.

The mutual inductance between two coils is $2.5 \mathrm{H}$. If the current in one coil is changed at the rate $2.0 {\mathrm{As}}^{-1}$, what will be the emf induced in the other coil?

In a car spark coil, an emf of $40,000 \mathrm{V}$ is induced in the secondary when the primary current changes from $4 \mathrm{A}$ to zero in $10 \mathrm{\mu s}$. Find the mutual inductance between the primary and secondary windings of this spark coil.

If the current in the primary circuit of a pair of coils changes from $10 \mathrm{A}$ to $0$ in $0.1 \mathrm{s}$, calculate the induced emf in the secondary if the mutual inductance between the two coils is $2 \mathrm{H}$.

If the current in the primary circuit of a pair of coils changes from $10 \mathrm{A}$ to $0$ in $0.1 \mathrm{s}$, calculate the change of flux per turn in the secondary if it has $500$ turns.

A conducting wire of $100$ turns is wound over $1 \mathrm{cm}$ near the centre of a solenoid of $100 \mathrm{cm}$ length and $2 \mathrm{cm}$ radius having $1000$ turns. Calculate the mutual inductance of the two coils.

A solenoid has $2000$ turns wound over a length of $0.3 \mathrm{m}$. The area of cross-section is $1.2\times {10}^{-3}{\mathrm{m}}^2$. Around its central section, a coil of $300$ turns is closely wound. If an initial current of $2 \mathrm{A}$ is reversed in $0.25 \mathrm{s}$, find the emf induced in the coil.

Calculate the mutual inductance between two coils if a current $10 \mathrm{A}$ in the primary coil changes the flux by $500 \mathrm{Wb}$ per turn in the secondary coil of $200$ turns. Also, determine the induced emf across the ends of the secondary coil in $0.5 \mathrm{s}$.