MCQ
An electromagnetic field exists only when there is.
- Aan increasing current
- Bdecreasing current
- Cvoltage
- ✓current
✓
Answer
Correct option: D.
current
An electromagnetic field exists only when there is current. electric current flowing through a wire caused a nearby compass to deflect. $...$ In most conductors, the magnetic field exists only as long as the current is flowing $($i.e. an electrical charge is in motion$).$
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