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Question
State two advantages of an electromagnet over a permanent magnet.
Solution
- An electromagnet can produce a strong magnetic field.
- The strength of the magnetic field of an electromagnet can easily be changed by changing the current in its solenoid.
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Choose the correct option:
Soft iron is used to make the core of the transformer because of its ______.
A thin diamagnetic rod is placed vertically between the poles of an electromagnet. When the current in the electromagnet is switched on, then the diamagnetic rod is pushed up, out of the horizontal magnetic field. Hence the rod gains gravitational potential energy. The work required to do this comes from ______.
Assertion: Electromagnetic are made of soft iron.
Reason: Coercivity of soft iron is small.
