Q. A charged particle is moving in a uniform magnetic field in a circular path. Radius of circular path is $R$. When energy of particle is doubled, then new radius will be
A) $R\sqrt{2}$
B) $R\sqrt{3}$
C) $2\ R$
D) $3\ R$
Explanation
(a) $r = \frac{\sqrt{2mK}}{qB} \Rightarrow r \propto \sqrt{K} \Rightarrow \frac{R}{R_{2}} = \sqrt{\frac{K}{2K}} \Rightarrow R_{2} = R\sqrt{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.