Electromagnetic Induction

An aeroplane, with its wings spread 10 m, is flying at a speed of 180 km/h in a horizontal direction. The total intensity of earth's field at that part is 2.5 $\times$ 10^$-$4 Wb/m² and the angle of dip is 60$^\circ$. The emf induced between the tips of the plane wings will be __________.

Which of the following units denotes the dimension ${{M{L^2}} \over {{Q^2}}}$, where $Q$ denotes the electric charge?

A coil of cross-sectional area A having n turns is placed in a uniform magnetic field B. When it is rotated with an angular velocity $\omega ,$ the maxium e.m.f. induced in the coil will be:

A conducting circular loop made of a thin wire, has area 3.5 $\times$ 10^$-$3 m² and resistance 10 $\Omega$. It is placed perpendicular to a time dependent magnetic field B(t) = (0.4T)sin(50$\pi$t). The field is uniform in space. Then the net charge flowing through the loop during t = 0 s and t = 10 ms is close to :

When the current changes from $+ 2A$ to $-2A$ in $0.05$ second, an $e.m.f.$ of $8$ $V$ is inducted in a coil. The coefficient of self- induction of the coil is

Two coils are placed close to each other. The mutual inductance of the pair of coils depends upon

A coil of inductance $300$ $mH$ and resistance $2\,\Omega$ is connected to a source of voltage $2$ $V$. The current reaches half of its steady state value in

An ideal coil of $10H$ is connected in series with a resistance of $5\Omega$ and a battery of $5V$. $2$ second after the connection is made, the current flowing in ampere in the circuit is

Two coaxial solenoids are made by winding thin insulated wire over a pipe of cross-sectional area $A=$ $10\,\,c{m^2}$ and length $=20$ $cm$ . If one of the solenoid has $300$ turns and the other $400$ turns, their mutual inductance is $\left( {{\mu _0} = 4\pi \times {{10}^{ - 7}}\,Tm\,{A^{ - 1}}} \right)$

Two coaxial solenoids of different radius carry current $I$ in the same direction. $\overrightarrow {{F_1}}$ be the magnetic force on the inner solenoid due to the outer one and $\overrightarrow {{F_2}}$ be the magnetic force on the outer solenoid due to the inner one. Then :

A small circular loop of wire of radius a is located at the centre of a much larger circular wire loop of radius b. The two loops are in the same plane. The outer loop of radius b carries an alternating current I = I_o cos ($\omega$t). The emf induced in the smaller inner loop is nearly :

There are two long co-axial solenoids of same length $l$. The inner and outer coils have radii r₁ and r₂ and number of turns per unit length n₁ and n₂, respectively. The ratio of mutual inductance to the self - inductance of the inner-coil is :

Two coils 'P' and 'Q' are separated by some distance. When a current of 3 A flows through coil 'P', a magnetic flux of 10^–3 Wb passes through 'Q'. No current is passed through 'Q'. When no current passes through 'P' and a current of 2 A passes through 'Q', the flux through 'P' is :-

The total number of turns and cross-section area in a solenoid is fixed. However, its length L is varied by adjusting the separation between windings. The inductance of solenoid will be proportional to :

A copper wire is wound on a wooden frame, whose shape is that of an equilateral triangle. If the linear dimension of each side of the frame is increased by a factor of 3, keeping the number of turns of the coil per unit length of the frame the same, then the self inductance of the coil:

The self induced emf of a coil is 25 volts. When the current in it is changed at uniform rate from 10 A to 25 A in 1s, the change in the energy of the inductance is -

The time taken for the magnetic energy to reach 25% of its maximum value, when a solenoid of resistance R, inductance L is connected to a battery, is :

An inductor coil stores 64 J of magnetic field energy and dissipates energy at the rate of 640 W when a current of 8A is passed through it. If this coil is joined across an ideal battery, find the time constant of the circuit in seconds :

A small square loop of side 'a' and one turn is placed inside a larger square loop of side b and one turn (b >> a). The two loops are coplanar with their centres coinciding. If a current I is passed in the square loop of side 'b', then the coefficient of mutual inductance between the two loops is :