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Question
A charged particle would continue to move with a constant velocity in a region wherein ______.
- E = 0, B ≠ 0.
- E ≠ 0, B ≠ 0.
- E ≠ 0, B = 0.
- E = 0, B = 0.
Options
a and c
b and d
a, b and d
c and d
Solution
a, b and d
Explanation:
This problem is based upon the single moving charge placed with some uniform electric and magnetic fields in space. Then they experience a force called Lorentz force is given by the relation Fnet = qE + q(v × B).
Force experience by the charged particle due to electric field Fe = qE
Force experience by the charged particle due to magnetic field, Fm = q(v × B)
According to the problem, particle is moving with constant velocity means the acceleration of particle is zero and also it is not changing its direction of motion.
This will happen when the net force on particle is zero.
- if E = 0, and v || B, then Fnet = 0.
- if E ≠ 0, B ≠ 0 and E, v and B are mutually perpendicular.
- When both E and B are absent.
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