At one instant an electron is moving in the positive x-direction in a region where there is a uniform magnetic field in the positive z direction. When viewed from a point on the positive z axis, it subsequent motion is:
Correct answer: C. Counterclockwise around a circle in the xy plane
- A. Straight ahead
- B. Clockwise around a circle in the xy plane
- C. Counterclockwise around a circle in the xy plane
- D. In the positive z direction
Explanation
F=e(VxB) As given v is in +ve x -direction B is in +ve z -direction By using right hand rule the magnetic force acts along the + y-axis. So. the electron will be deflected along +y-axis and will trace a curve path in xy-plane (counter clockwise).
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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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