Advertisements
Advertisements
प्रश्न
Name the material used for making the armature of an electric bell. Give a reason for your answer.
Advertisements
उत्तर
The material used for making the armature of an electric bell is soft iron which can induce magnetism rapidly.
APPEARS IN
संबंधित प्रश्न
State two ways of magnetising an iron piece?
The magnetic flux through a coil having 100 turns decreases from 5 milli weber to zero in 5 second. Calculate the e.m.f. induced in the coil.
State two factors on which the strength of induced e. m.f. depends.
State the two properties of the magnetic lines of force around a circular coil.
Describe a simple Experiment to demonstrate that there Exists a magnetic field around a current-carrying conductor.
State the purpose of the iron core.
How does a magnetic field set up by a solenoid change when number of turns are increased?
State the principle of a D. C. motor.
The primary windings of a step-up transformer are usually made of thicker wire than the secondary. Explain.
(i) A straight wire conductor passes vertically through a piece of cardboard sprinkled with iron filings. Copy the diagram and show the setting of iron filings when a current is passed through the wire in the upward direction and the cardboard is tapped gently. Draw arrows to represent the direction of the magnetic field lines.

(ii) Name the law which helped you to find the direction of the magnetic field lines.
