Embibe Experts Solutions for Chapter: Electromagnetic Induction, Exercise 2: Exercise 2

When the current $i$ in a certain inductor coil is $5.0 \mathrm{A}$ and is increasing at the rate of $10.0 \mathrm{A} {\mathrm{s}}^{-1}$, the potential difference across the coil is $140 \mathrm{V}$. When the current is $5.0 \mathrm{A}$ and decreasing at the rate of $10.0 \mathrm{A} {\mathrm{s}}^{-1}$, the potential difference is $60 \mathrm{V}$. The self inductance of the coil is -

A coil of resistance $400 \mathrm{\Omega }$ is placed in a magnetic field. If the magnetic flux $\varphi \left(\mathrm{Wb}\right)$ linked with the coil varies with time $t \left(\mathrm{s}\right)$ as $\varphi =50t^2+4.$ The current in the coil at $t=2 \mathrm{s}$ is

A superconducting loop of radius $R$ has self inductance $L$. A uniform and constant magnetic field $B$ is applied perpendicular to the plane of the loop. Initially current in this loop is zero. The loop is rotated by $180°.$ The current in the loop after rotation is equal to-

A generator has an $\mathrm{e}.\mathrm{m}.\mathrm{f}.$ of $440 \mathrm{V}$ and internal resistance of $400 \mathrm{\Omega }$. Its terminals are connected to a load of $4000 \mathrm{ohm}$. The voltage across the load is

A $50$ $\mathrm{turns}$ circular coil has radius $3 \mathrm{cm}$. It is kept in a magnetic field$\left(B\right)$ acting normal to the area of the coil. The magnetic field $B$ is increased from $0.10$ $\mathrm{T}$ to $0.35$ $\mathrm{T}$ in $2$ $\mathrm{ms}$. The average induced emf in the coil is

A solenoid has $2000$ $\mathrm{turns}$ wound over a length of $0.30 \mathrm{m}$. The area of its cross-section is $1.2\times {10}^{-3} {\mathrm{m}}^2$. Around its central section, a coil of $300$ $\mathrm{turn}$ is wound. If an initial current of $2 \mathrm{A}$ in the solenoid is reversed in $0.25 \mathrm{s},$ then the emf induced in the coil is

A small square loop of wire of side is placed inside a large square loop of wire of side $L\left(L>>l\right)$. The loops are co-planar and their centres coincide. The mutual inductance of the system is proportional to

A coil of area $7 {\mathrm{cm}}^2$ and of $50$ turns is kept with its plane normal to a magnetic field $B$. A resistance of $30 \mathrm{ohm}$ is connected to the resistance less coil. $B$ is $75\exp \left(-200t\right)$ gauss. The current passing through the resistance at $t=5$ $\mathrm{ms}$ will be-