If a wire having current 10A has a 3T magnetic field, what will be the magnetic field at a point from the wire at double the distance?
Correct answer: A. Reduces by factor 2
- A. Reduces by factor 2
- B. Becomes double
- C. Reduces by factor 4
- D. Becomes triple
Explanation
Any current-carrying wire is surrounded by the magnetic field which is B = µ0I/2πr. It can be seen from the above equation that the magnetic field is inversely proportional to the distance and directly proportional to the current. When the distance from the wire becomes double, the magnetic field will reduce by a factor of two, which is 1.5 T.
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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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