Easy MCQ +4 / -1 PYQ · JEE Mains 2022

A charge particle moves along circular path in a uniform magnetic field in a cyclotron. The kinetic energy of the charge 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 charge particle :

  1. A 1 : 1
  2. B 1 : 2
  3. C 2 : 1 Correct answer
  4. D 1 : 4

Solution

<p>$R = {{mv} \over {Bq}} = {{\sqrt {2mK} } \over {Bq}}$</p> <p>$\Rightarrow R \propto \sqrt K$</p> <p>$\Rightarrow$ ratio = 2 : 1</p>

About this question

Subject: Physics · Chapter: Magnetic Effects of Current · Topic: Biot-Savart Law

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