JEE Advanced · Physics · 20. Magnetism & Current
A uniform magnetic field B exists in the region between and (region 2 in the figure) pointing normally into the plane of the paper. A particle with charge and momentum p directed along -axis enters region 2 from region 1 at point Which of the following option(s) is/are correct?

- A For , the particle will enter region 3 through the point on -axis
- B For , the particle will re-enter region 1
- C For a fixed B, particles of same charge Q and same velocity , the distance between the point and the point of re-entry into region 1 is inversely proportional to the mass of the particle
- D When the particle re-enters region 1 through the longest possible path in region 2, the magnitude of the change in its linear momentum between point and farthest point from -axis is
Answer & Solution
Correct Answer
(B) For , the particle will re-enter region 1
Step-by-step Solution
Detailed explanation
For radius of path
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