A bar magnet is moved toward a coil of 50 turns at 0.5 m/s, changing the magnetic flux at a rate of 0.02 Wb/s. According to Lenz's law, the direction of the induced current in the coil is such that it:
Correct answer: B. Repels the magnet
- A. Attracts the magnet
- B. Repels the magnet
- C. Does not affect the magnet
- D. Rotates the magnet
Explanation
Lenz's law states that the induced current opposes the change in magnetic flux. As the magnet approaches, flux increases, so the induced current creates a magnetic field opposing the magnet's motion, repelling it.
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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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