JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
A charged particle moves along circular path in a uniform magnetic field in a cyclotron. The kinetic energy of the charged particle increases to \(4\) times its initial value. What will be the ratio of new radius to the original radius of circular path of the charged particle
- A \(1: 1\)
- B \(1: 2\)
- C \(2: 1\)
- D \(1: 4\)
Answer & Solution
Correct Answer
(C) \(2: 1\)
Step-by-step Solution
Detailed explanation
radius of paerticle in cyclotron \(r =\frac{\sqrt{2 mK . E .}}{ qB }\) So ratio of new radius to original \(\frac{ r _{ n }}{ r _{0}}=\sqrt{\frac{( K \cdot E .)_{ n }}{( K \cdot E )_{0}}}=\sqrt{4} \Rightarrow 2: 1\)
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