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Question
When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.
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Solution
- When current flows through the wire, it deflects the compass near it from its north-south orientation, much like a magnet. This is known as the magnetic effect of the current.
- We know that the compass needle is constructed of a thin magnet. When this needle touches another magnet, the similar poles repel each other while the opposing poles attract each other.
- So the deflection is visible in the needle. In this situation, the wire acts as a magnet, causing deflection in the needle of the compass.
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