# Electromagnetic Induction

## Magnetic compass needle will be deflecting if it is kept near

A.Static charge B.Soft iron C.Semi-conductor D.Accelerating charge

## The alternating current has frequency of 106 Hz in such a way that time period for completion of cycle is

A.1?s B.1.5?s C.106sec D.1sec

## Long distance transmission is easy for

A.D.C voltage B.A.C voltage C.Half A.C voltage D.Half D.C voltage

## Which one of the following devices does not function like an electric motor?

A.Galvanometer B.Ammeter C.Voltmeter D.Transformer

## The out put voltage of a transformer is 3 times the input voltage then turns ratio will be

A.3-Jan B.3 C.1 D.6

## If the secondary coil has Ns turns and the primary Np turns the relation between secondary and primary voltages is given by

A.Vs/Vp = Np/Ns B.Vs/Vp = Ns/Np C.Vp/Vs = Ns/Np D.Vp/Vs = Np/Ns

## For long distance transmission the transformer used is

A.Step down B.Input voltage and output voltage remain same C.Step up D.Amplifier is used

## Power loss in actual transformer is due to

A.Small output B.Eddy currents and magnetic hysterias C.Soft iron core D.Back emf

## Self inductance of a long solenoid is

A.??n2?A B.??n2A/? C.??N2?A D.BA

## A metal rod of 25 cm length is moving at a speed of 0.5/sec in direction perpendicular to 0.25T magnetic field. Emf produced in the rod is

A.0 volt B.3.125 volt C.31.25 volt D.0.03125 volt