A long straight wire carries a current from east to west.A magnetic compass is placed 1meter directly north of the wire at the same horizontal level.Which direction will the north pole of the compass needle point due to magnetic field of the wire?
Correct answer: B. South
- A. North
- B. South
- C. East
- D. West
Explanation
Use right-hand rule: thumb current (west), fingers → magnetic field. At a point north of the wire, the field points south. Compass needle aligns with the field north pole points → South.
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Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
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