Electromagnetic Induction

The north pole of the magnet is brought near a metallic ring as shown in figure. The direction of induced current in the ring (if looked from upside) will be

The variation of induced emf (E) with time (t) in a coil if a short bar magnet is moved along its axis with a constant velocity is best represented as $\{$North pole is situated at left end of the bar magnet and South…

A thin semicircular conducting ring (PQR) of radius r is falling with its plane vertical in a horizontal magnetic field B as shown in the figure. The potential difference developed across the ring when its speed is v,…

A thin semicircular conducting ring of radius R is falling with its plane vertical in a horizontal magnetic induction B. At the position MNQ the speed of ring is V and emf developed across the ring is

The current in a primary coil of a step-down transformer having $N_p$ turns is given by $i = i_0 \cos\omega t$. The secondary coil of having $N_s$ turns is wound over the primary coil. The emf induced in the secondary is

In an a.c. generator, a rectangular coil of $1000$ turns each having area $\dfrac{10^{-2}}{\pi}\ \text{m}^2$ is rotated at $180$ r.p.m. about an axis perpendicular to a uniform magnetic field of magnitude $2$ T. The…

The value of mutual inductance of two coils is $6$ mH. The current in one of the coil changes from $7$ A to $2$ A in $0.2$ second, so that e.m.f. is induced in the other coil. If the resistance of the coil is $6\…

Identify the CORRECT statement

The self-inductance L of a toroid having circular cross-section of radius $r$ and major radius $R$ is ($r \ll R$)

A magnetic field induction is changing in magnitude at a constant rate $\dfrac{dB}{dt}$. The plane of a circular loop of radius $r$ of copper wire (mass $m$ and radius $a$) is placed perpendicular to the field. The…

When four inductors of the same inductances L are connected in series, and I is the current passing through the circuit. The energy stored in the circuit is

Semicircular wire of radius R is rotated in a uniform magnetic field about an axis passing through its ends. If the frequency of rotation is f, the amplitude of induced e.m.f. in the wire is [B$=$magnetic field…