What is an electromagnet? On factors does the strength of an electromagnet depend?
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What is an electromagnet? Draw a circuit diagram to show how a soft iron piece can be transformed into an electromagnet.
Electromagnet: A soft iron core placed inside a solenoid behaves like a powerful magnet when a current is passed through the solenoid. This device is called an electromagnet. When the current is switched off, the iron core loses its magnetism and so it is no longer an electromagnet. Thus, electromagnets are temporary magnets.
Fig. Electromagnet (a) Bar type (b) Horse-shoe type
Factors on which the strength of an electromagnet depends:
(i) Number of turns in the coil: The larger the number of turns in the coil, greater is the strength of the electromagnet.
(ii) Strength of the current: The larger the current passed through the solenoid, more powerful is the electromagnet.
(iii) Nature of the core material: The core of the magnetic material like soft iron increases the strength of the electromagnet.
