Electromagnetic Induction - Electromagnetism - Physics Previous Year Questions

A coil of resistance $8 \Omega$, number of turns 250 and area $120 \mathrm{~cm}^2$ is placed in a uniform magnetic field of 2 T such that the plane of the coil makes and angle of $\frac{\pi}{6}$ with the direction of the magnetic field. In a time of 100 ms , the coil is rotated until its plane becomes parallel to the direction of the magnetic field. The current induced in the coil is

The plane of a circular coil of resistance $7.5 \Omega$ is placed perpendicular to a uniform magnetic field. The flux $\phi$ (in weber) through the coil varies with time $t$ (in second) as $\phi=2 t^2+3 t-2$. The induced power in the coil at time $t=3 \mathrm{~s}$ is

An emf of 2.8 mV is induced in a rectangular loop of area $150 \mathrm{~cm}^2$ when the current in the loop changes from 3 A to 8 A in a time of 0.2 s . Then, the self-inductance of the loop is

A circular coil of area $3 \times 10^{-2} \mathrm{~m}^2, 900$ turns and a resistance of $1.8 \Omega$ is placed with its plane perpendicular to a uniform magnetic field of $3.5 \times 10^{-5} \mathrm{~T}$. The current induced in the coil when it is rotated through $180^{\circ}$ in half a second is

The small energy losses in transformers due to eddy currents can be reduced by

A coil of resistance $16 \Omega$ is placed with its plane perpendicular to a uniform magnetic field whose flux ( $\phi$ in $10^{-3}$ weber) changes with time ( $t$ in second) as $\phi=5 t^2+4 t+2$. The induced current at time $t=6$ second is

The radius of a coil of $N$ turns is $R$. If the plane of the coil is placed parallel to a uniform magnetic field $B$, then the flux linked with the coil is