JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
An electron, a proton and an alpha particle having the same kinetic energy are moving in circular orbits of radii \(r_e,r_p\) and \({r_\alpha }\) respectively in a uniform magnetic field \(B\). The relation between \(r_e,r_p\) and \(\;{r_\alpha }\) is
- A \(r_e < r_p\) \(=\) \(\;{r_\alpha }\)
- B \(r_e < r_p\) \( <\) \(\;{r_\alpha }\)
- C \(r_e < \) \(\;{r_\alpha }\) \(< r_p\)
- D \(r_e > r_p\) \(=\) \(\;{r_\alpha }\)
Answer & Solution
Correct Answer
(A) \(r_e < r_p\) \(=\) \(\;{r_\alpha }\)
Step-by-step Solution
Detailed explanation
As we know, radius of circular path in magnetic field \(\mathrm{r}=\frac{\sqrt{2 \mathrm{Km}}}{\mathrm{qB}}\) For electron, \(\mathrm{r}_{\mathrm{e}}=\frac{\sqrt{2 \mathrm{Km}_{\mathrm{e}}}}{\mathrm{eB}}.........(i)\) For proton,…
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