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The angular speed of the charged particle is independent of ______.

Asked in GSEB Board March 2018 · Circular motion: radius, period and energy

Answer: (2) its linear speed

Step-by-step solution

Idea: in a uniform magnetic field the magnetic force supplies the centripetal force, qvB=(mv²)/r, so r=(mv)/(qB).

Angular speed: ω=v/r=v×(qB)/(mv)=(qB)/m.

The speed cancels: a faster particle simply travels on a proportionally larger circle and takes exactly the same time to go round.

So ω depends on the charge, the field and the mass, but not on the linear speed.

Why the other options are wrong

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