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Question
The direction of current flowing in the coil of an electromagnet at its two ends X and Y are as shown below:
What is the polarity of end X?
What is the polarity of end Y?
Name and state the rule which you have used to determine the polarities.
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Solution
The polarity of end X is south because current is flowing in clockwise direction at this end.
The polarity of end Y is north because current is flowing in anticlockwise direction at this end.
We have used clock face rule to determine the polarities.
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