Q. A charged particle of mass $m$ and charge $q$ describes circular motion of radius $r$ in a uniform magnetic field of strength $B$. The frequency of revolution is
A) $\frac{Bq}{2\pi m}$
B) $\frac{Bq}{2\pi rm}$
C) $\frac{2\pi m}{Bq}$
D) $\frac{Bm}{2\pi q}$
Explanation
(a) Time period is given by $T = \frac{2\pi m}{qB}$
$\Rightarrow$ Frequency $v = \frac{1}{T} = \frac{qB}{2\pi m}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.