A circular coil of radius 0.05 m with 20 turns moves at 2 m/s perpendicular to a magnetic field of 0.4 T. The motional emf induced across its ends is:
Correct answer: C. 1.6 V
- A. 0.4 V
- B. 0.8 V
- C. 1.6 V
- D. 3.2 V
Explanation
Motional emf = ε = BlvN, where l is the length of the conductor moving perpendicular to the magnetic field. For a circular coil, this length is the diameter 2r. Substituting values, ε= 20x0.4x0.1x2= 1.6V.
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About Electromagnetism
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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