Question
Under what conditions permanent electromagnet is obtained if a current carrying solenoid is used? Support your answer with the help of a labelled circuit diagram.
✓
Answer
Permanent electromagnet is obtained if:
- Direct current flows through the solenoid and
- Steel rod (a magnetic substance) is placed inside the solenoid.
In other words, a steel rod can be made a permanent electro-magnet if it is placed inside a solenoid carrying direct current as shown in figure.
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