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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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प्रश्न

When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.

संक्षेप में उत्तर
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उत्तर

  • 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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अध्याय 10: Electric Current and Its Effects - Exercises [पृष्ठ १२०]

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एनसीईआरटी Science [English] Class 7
अध्याय 10 Electric Current and Its Effects
Exercises | Q 6. | पृष्ठ १२०

संबंधित प्रश्न

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  • Take a small aluminium rod AB (of about 5 cm). Using two connecting wires suspend it horizontally from a stand, as shown in Fig.
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  • Connect the aluminium rod in series with a battery, a key and a rheostat.
  • Now pass a current through the aluminium rod from end B to end A.
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  • Reverse the direction of current flowing through the rod and observe the direction of its displacement. It is now towards the right.
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