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Question
Which of the following particles will have minimum frequency of revolution when projected with the same velocity perpendicular to a magnetic field?
Options
Electron
Proton
He+
Li+
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Solution
Li+
Time period of the revolution of the particle, `T = (2pim)/(qB)`
As frequency is the reciprocal of time period, so `f =(qB)/(2pim)`
The charge on all the four particles is same. But the mass is maximum for Li+. So, it will have the smallest frequency of revolution.
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