JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
A cyclotron is used to accelerate protons. If the operating magnetic field is \(1.0\,T\) and the radius of the cyclotron 'dees' is \(60 cm\), the kinetic energy of the accelerated protons in \(MeV\) will be. [use \(m _{p}=1.6 \times 10^{-27} kg , e =1.6 \times 10^{-19} C\) ]
- A \(12\)
- B \(18\)
- C \(16\)
- D \(32\)
Answer & Solution
Correct Answer
(B) \(18\)
Step-by-step Solution
Detailed explanation
Kinetic energy of electron in cyclotron \(=\left[\frac{ q ^{2} B ^{2} r _{0}^{2}}{2 m }\right]\) \(=18\,MeV\)
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