MCQ
When current passes through the circuit a compass needle rests in which direction (with respect to the Earth)?
- ASouth - north
- BNorth - south
- CEast - west
- DWest - east
✓
Answer
- South - north
Explanation:
The earth acts like a huge magnet. Thus in the absence of electric current a compass needle always comes to rest in Earths North - south direction.
However, when current passes through the circuit the needle comes to rests in the direction opposite to the magnetic field of Earth i.e. South-North direction.
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