A particle of mass m and charge q moves with a constant velocity v along the positive x direction. It enters a region containing a uniform magnetic field B directed along the negative z direction, extending from x = a to x = b. The minimum value of v required so that the particle can just enter the region x>b is:
Correct answer: B. Option B
- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation
Width of the magnetic field region (b − a) ≤ R ; where 'R' is its radius of curvature inside magnetic field.∴ R = mv / qB = (b − a) ⇒ v = (b − a) q B / m.
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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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