Electromagnetic Induction - Electricity - Physics Previous Year Questions

A long solenoid of radius a and number of turns per unit length \(n\) is enclosed by cylindrical shell of radius R, thickness \(d\) \((d < < R)\) and length L. A variable current \(\mathrm{I}=\mathrm{I}_{0} \sin \omega t\) flows through the coil. If the resistivity of the material of cylindrical shell is \(\mathrm{P}\), find the induced current in the shell.

Which force causes the train to elevate upwards

What is the disadvantage of this system?

What is the advantage of this system?

The figure shows certain wire segments joined together to form a coplanar loop. The loop is placed in a perpendicular magnetic field in the direction going into the plane of the figure. The magnitude of the field increases with time. \(I_1\) and \(I_2\) are the currents in the segments ab and cd. Then,

Two metallic rings A and B, identical in shape and size but having different resistivities \(\rho_A\) and \(\rho_B\), are kept on top of two identical solenoids as shown in the figure below. When current I is switched on in both the solenoids in identical manner, the rings A and B jump to heights \(h_A\) and \(h_B\), respectively, with \(h_A > h_B\). The possible relation(s) between their resistivities and their masses \(m_A\) and \(m_B\) is (are)

A circular wire loop of radius R is placed in the xy plane centred at the origin O. A square loop of side a(a << R) having two turns is placed with its centre at z = \(\sqrt3\)R along the axis of the circular wire loop, as shown in the figure. The plane of the square loop makes an angle of 45\(^\circ\) with respect to z-axis. If the mutual inductance between the loops is given by \({{{\mu _0}{a^2}} \over {{2^{p/2}}R}}\), then the value of p is ___________.

A current carrying infinitely long wire is kept along the diameter of a circular wire loop, without touching it, the correct statement(s) is(are)

A region in the form of an equilateral triangle (in $x-y$ plane) of height $L$ has a uniform magnetic field $\vec{B}$ pointing in the $+z$-direction. A conducting loop $\mathrm{PQR}$, in the form of an equilateral triangle of the same height $L$, is placed in the $x-y$ plane with its vertex $\mathrm{P}$ at $x=0$ in the orientation shown in the figure. At $t=0$, the loop starts entering the region of the magnetic field with a uniform velocity $\vec{v}$ along the $+x$-direction. The plane of the loop and its orientation remain unchanged throughout its motion.

Which of the following graph best depicts the variation of the induced emf $(E)$ in the loop as a function of the distance $(x)$ starting from $x=0$ ?