Advertisements
Advertisements
Question
State two factors on which the strength of induced e. m.f. depends.
Advertisements
Solution
(i) The time of change of magnetic flux, (ii) The strength of magnetic field.
RELATED QUESTIONS
Show with the aid of a diagram how a wire is wound on a U-shaped piece of soft iron in order to make it an electromagnet. Complete the circuit diagram and label the poles of the electromagnet.
State two differences between an electromagnet and a permanent magnet.
Name the type of transformer shown in fig . What changes will you observe regarding the brightness of the lamp, if
(a) The no. of turns in the secondary is doubled?
(b) The part X of the transformer is removed?
( c) The core of the transformer is made out of copper?
(d ) The A.C. supply is replaced by D.C.?
What is an electromagnet?
State the purpose of the iron core.
State two advantages of an electromagnet over a bar magnet.
What will be the effect on the working of an electric bell if instead of a direct current an alternating current is used?
State the factors that can increase the speed of rotation of the coil in a D.C. motor.
How does a magnetic field set up by a solenoid change when cross-sectional area of solenoid is increased?
Which magnet will you use?
Iron is to be separated from trash.
