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प्रश्न
Why is soft iron used as the core of the electromagnet in an electric bell?
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उत्तर
The soft iron bar acquires the magnetic properties only when an electric current flows through the solenoid and loses the magnetic properties as the current is switched off. Hence, soft iron is used as the core of the electromagnet in an electric bell.
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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.
Name the material used for preparing an electromagnet.
How is an electromagnet made? Name two factors on which the strength of magnetic field of the electromagnet depends.
You are required to make an electromagnet from a soft iron bar by using a cell, an insulated coil of copper wire and a switch.
- Draw a circuit diagram to represent the process.
- Label the poles of the electromagnet.
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 ways through which the strength of an electromagnet can be increased.
State two advantages of an electromagnet over a permanent magnet.
State two differences between an electromagnet and a permanent magnet.
Name the material used for making the armature of an electric bell. Give a reason for your answer.
Unlike magnetic poles ______ whereas like poles ______.
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.
Explain the working of the following device.
Speaker
Explain the working of the following device.
Magnetic levitation trains.
