An electron is moving north in a region where the magnetic field is south. The magnetic force exerted on the electron is:
Correct answer: A. Zero
- A. Zero
- B. Up
- C. Down
- D. East
Explanation
The magnetic force on a charged particle is given by F = qvB sin(θ), where θ is the angle between the velocity and the magnetic field. Since the electron is moving north and the field is south, they are anti-parallel, and the angle is 180°. As sin(180°) = 0, the magnetic force is zero.
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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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