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Question
Which of the following particles will experience maximum magnetic force (magnitude) when projected with the same velocity perpendicular to a magnetic field?
Options
Electron
Proton
He+
Li++
Solution
Li++
Force on a moving charged particle,
F = qVBsin θ
As velocity V and magnetic field B are constant, and angle between the magnetic field and charged particle is 90° , the only thing on which force F depends is charge q.
Now, the charge on Li++ charge on electron, proton or He+ . So the force is maximum for Li++.
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