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प्रश्न
Name the material used for making the armature of an electric bell. Give a reason for your answer.
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उत्तर
The material used for making the armature of an electric bell is soft iron which can induce magnetism rapidly.
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संबंधित प्रश्न
Why is soft iron used as the core of the electromagnet in an electric bell?
Name one device that uses an electromagnet.
Electromagnets are made up of :
The following figure shows a coil wound around a soft iron bar XY.
- State the polarity at the ends X and Y as the switch is pressed.
- Suggest one way of increasing the strength of electromagnet so formed.
A coil of insulated copper wire is wound around a piece of soft iron and current is passed in the coil from a battery. What name is given to the device so obtained? Give one use of the device mentioned by you.
State two advantages of an electromagnet over a permanent magnet.
State two differences between an electromagnet and a permanent magnet.
Explain, why steel is used in preference to soft iron for making permanent magnets while soft iron is used in preference to steel for making electromagnets.
What is an electroscope? Describe the different stages of charging a gold leaf electroscope negatively with the help of a diagram.
Assertion (A): When 2 long parallel wires, hanging freely are connected in parallel to a battery, they come closer to each other.
Reason (R): Wires carrying current in opposite directions repel each other.
