Electromagnetic...

A dynamo converts

A coil of wire is arranged with its plan perpendicular to a uniform magnetic field o flux density B. when the radius of the coil increases from r1 to r2 in time ?t then what is the emf induced in the coil?

If the coil is wound on an iron core the flux through it will

A short - circuited coil is placed in a time - varying magnetic field . Electrical power is dissipated due to the current induced in the coil . If the number of turns were to be quadrupled and the coil radius halved . The electrical power dissipated would be

A conductor 2 meters long moves at right angles to a magnetic field of flux density 1 tesla with a velocity of 12.5 m/s . The induced e.m.f. in the conductor will be

Weber is the unit of

In case of an inductance , current is proportional to

Transformer works on the principle of

Two coils have inductances of 8 mH and 18 mH and a co - efficient of coupling of 0.5 . If the two coils are connected in series aiding , the total inductance will be

A conducting gas is in the from of a long cylinder . Current flows through the gas along the length of the cylinder . The current is distributed uniformly across the cross - section of the gas . Disregard thermal and electrostatic forces among the gas molecules . Due to the magnetic set up inside the gas and the forces which they exert on the moving ions , the gas will tend to