Which one of the following devices does not function like an electric motor ?
A. Galvanometer
B. Ammeter
C. Voltmeter
D. Transformer
For long distance transmission the transformer used is_____________?
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
Lagging of changes in the magnetization of a substance behind changes in the magnetic field as the magnetic field is varied is known as magnetic_____________?
Lagging of changes in the magnetization of a substance behind changes in the magnetic field as the magnetic field is varied is known as magnetic_____________?
A. Retaintivity
B. Permeability
C. Flux
D. Hysteresis
When the motor is at its maximum speed then back emf will be______________?
When the motor is at its maximum speed then back emf will be______________?
A. Maximum
B. Zero
C. Intermediate values
D. No back emf
Transformer works on the principle of________________?
Transformer works on the principle of________________?
A. Lenzs law
B. Faradays law
C. Mutual induction
D. Law of conservation of power
An electric current induced within the body of a conductor when that conductor either moves through a non uniform magnetic field or in a region where there is a change in magnetic flux is called_____________?
An electric current induced within the body of a conductor when that conductor either moves through a non uniform magnetic field or in a region where there is a change in magnetic flux is called_____________?
A. Induced current
B. Eddy current
C. Back emf
D. None of the above
The out put voltage of a transformer is 3 times the input voltage then turns ratio will be________________?
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
Long distance transmission is easy for________________?
Long distance transmission is easy for________________?
A. D.C voltage
B. A.C voltage
C. Half A.C voltage
D. Half D.C voltage
Magnetic compass needle will be deflecting if it is kept near________________?
Magnetic compass needle will be deflecting if it is kept near________________?
A. Static charge
B. Soft iron
C. Semi-conductor
D. Accelerating charge
A.C can not be used for_______________?
A.C can not be used for_______________?
A. producing heat
B. producing light
C. Magnetizing iron
D. Producing magnetic field