
Concept explainers
In Figure Q24.1, suppose the magnet on the right is fixed in place and the magnet on the left is free to pivot about its center. Will the magnet on the left start to rotate? If so, will it initially rotate clockwise or counterclockwise?
Figure Q24.1

To check: the left side magnet’s rotation and find the initial rotating direction of this magnet.
Answer to Problem 1CQ
The left side magnet starts rotating and it is rotating in the direction of clockwise.
Explanation of Solution
Given data:
Refer Figure Q24.1 in the textbook for two magnet arrangement.
Consider that the north pole of the magnet is expressed as “N” and the south pole of the magnet is expressed as “S”.
Explanation:
Consider the same poles of magnets repel each other and opposite poles of magnets attract each other.
The magnet, which is placed in the left side, will rotate in direction of clockwise because two N poles of the two magnets repel each other and the N pole of left magnet gets attracted by the S pole of right magnet. Then, the left magnet’s S pole is attracted to the N pole of the fixed magnet.
Therefore, the left magnet gets rotating due to opposite poles attraction and same poles repel.
Conclusion:
Thus, the left side magnet starts rotating and it is rotating in the direction of clockwise.
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