Physics
Grade-10
Easy
Question
Which of the following should be used as the core of an electromagnet?
- Hard iron
- Rusted iron
- Plastic
- Soft iron
Hint:
- An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil.
The correct answer is: Soft iron
- An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil.
- The most suitable material to be used as the core of an electromagnet is soft iron and it has high permeability but its availability and cost makes it uneconomical.
- The soft iron bar acquires the magnetic properties only when an electric current flows through the solenoid and loses the magnetic properties as soon as the current is switched off. That's why soft iron is used as the core of the electromagnet
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