COMEDK · Physics · 21. Magnetic Effects of Current
Electron of mass \(m\) and charge \(q\) is travelling with a speed \(v\) along a circular path of radius \(r\) at right angles to a uniform magnetic field of intensity \(B\). If the speed of the electron is doubled and the magnetic field is halved, then the resulting path would have a radius
- A \(2 r\)
- B \(4 r\)
- C \(\frac{r}{4}\)
- D \(\frac{r}{2}\)
Answer & Solution
Correct Answer
(B) \(4 r\)
Step-by-step Solution
Detailed explanation
We know that, radius of charge particle of mass \(m\) having charge \(q\) moving with speed \(v\) in magnetic field perpendicular to it, \(r=m v / B q...(i)\) For second case,…
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