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Question
What conclusion is drawn regarding the magnetic field at a point if a compass needle at that point rests in any direction? Give reason for your answer.
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Solution
If a compass needle rests in any direction (i.e., it does not align consistently in one direction), then the magnetic field at that point is zero or very weak.
A compass needle aligns itself along the direction of the net magnetic field present at a point (typically Earth's magnetic field). If no magnetic field is present, or if two or more magnetic fields cancel each other out, the needle has no preferred direction and may rest in any random position.
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