Electromagnetic...

When the current in a coil changes from 2 amp. to 4 amp. in 0.05 sec., an e.m.f. of 8 volt induced in the coil. The coefficient of self inductance of the coil is

A copper disc of radius $$0.1$$ $$m$$ rotated about its centre with $$10$$ revolutions per second in a uniform magnetic field of $$0.1$$ tesla with it's plane perpendicular to the field. The e.m.f. induced across the radius of disc is:

Magnetic flux $$\phi$$, in weber, in a closed circuit of resistance $$10\Omega$$ varies with time $$t$$ in seconds as $$\phi=6t^2-5t+1$$. The magnitude of induced current at $$t=0.25 s$$ is :

The coefficient of mutual inductance between two coils depends on

The current in a coil of $$L=40 mH$$ is to be increased uniformly from $$1A$$ to $$11A$$ in $$4$$ milliseconds. The induced e.m.f. will be

A student connects a coil of wire with a sensitive galvanometer as shown in figure. He will observe the deflection in the galvanometer if bar magnet is:

A square loop of side a is rotating about its diagonal with angular velocity $$\omega$$ in a perpendicular magnetic field $$\vec B$$. It has 10 turns. The emf induced is

A horizontal telegraph wire $$0.5\  km$$ long running east and west in a part of a circuit whose resistance is $$2.5\ \Omega$$. The wire falls to $$g=10.0\ m/s^2$$ and $$B=2\times 10^{-5} weber/m^2$$, then the current induced in the circuit is

Which of the following units denotes the dimension $$\dfrac {ML^2}{Q^2}$$ where Q denotes the electric charge?

A wire loop is rotated in a uniform magnetic field about an axis perpendicular to the field. The direction of the current induced in the loop reverse once each