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प्रश्न
The strength of the electromagnet can be increased by
पर्याय
reversing the directions of current
using alternating current of high frequency
increasing the current in the coil
decreasing the number of turns of coil
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उत्तर
The strength of the electromagnet can be increased by increasing the current in the coil
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संबंधित प्रश्न
Name one device that uses an electromagnet.
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.
State two advantages of an electromagnet over a permanent magnet.
State two differences between an electromagnet and a permanent magnet.
Why is soft iron used as the core of the electromagnet in an electric bell?
Name the material used for making the armature of an electric bell. Give a reason for your answer.
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.
Explain in detail the application of electromagnets.
Unlike magnetic poles ______ whereas like poles ______.
Explain the working of the following device.
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