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प्रश्न
Name the material used for making the armature of an electric bell. Give a reason for your answer.
What material is used for making the armature of an electric bell? Give a reason for using this material.
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उत्तर
The material used for making the armature of an electric bell is soft iron, which can induce magnetism rapidly.
संबंधित प्रश्न
Tick the most appropriate answer.
Which of the following methods is used to magnetize a magnetic without touching it by a magnet?
Name and state the rule by which polarity at the ends of a current carrying solenoid is determined.
What is an electric motor?
principle of an electric motor ?
Name the material of core in (a) an electric bell, (b) electromagnet, (c) a d.c. motor, (d) an a.c. generator and (e) a transformer.
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.?
State two advantages of an electromagnet over a bar magnet.
State the factors that can increase the speed of rotation of the coil in a D.C. motor.
The primary windings of a step-up transformer are usually made of thicker wire than the secondary. Explain.
State the factors, on which depends the magnitude of the force acting on current carrying conductor, when it is kept in a magnetic field perpendicular to it.
