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Objective Questions:
1. What should be the core of an electromagnet?
(a) soft iron
(b) hard iron
(c) rusted iron
(d) none of above

2. The best material to make permanent magnets is
(a) aluminium
(b) soft iron
(c) copper
(d) alnico

3. Material of the core of a strong magnet is
(a) aluminium
(b) soft iron
(c) copper
(d) steel

4. Assertion: Steel core is used as an electromagnet.

Reason: Steel gets permanently magnetised when the current flows through the
coil wound around.

5. Assertion: Strength of an electromagnet depends on the magnitude of current
flowing through them.

Reason: Electromagnets are majorly used for lifting heavy weights.

6. Assertion: It is easier to bring North pole of a magnet to South pole of other
magnet.

Reason: There is a force of attraction between unlike poles of magnet.

Subjective Questions:

1. How does the strength of the magnetic field of an electromagnet depend on:
a) Current in the coil b) Number of turns of the coil.

2. How is an electromagnet different from a solenoid?
3. Mention at least three differences between an electromagnet and a permanent

magnet?
4. Write few uses of electromagnet.