JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
In an experiment, electrons are accelerated, from rest, by applying, a voltage of \(500 \,V.\) Calculate the radius of the path if a magnetic field \(100\,mT\) is then applied. [Charge of the electron \(= 1.6 \times 10^{-19}\,C\) Mass of the electron \(= 9.1 \times 10^{-31}\,kg\) ]
- A \(7.5\times 10^{-3}\,m\)
- B \(7.5\times 10^{-2}\,m\)
- C \(7.5\,m\)
- D \(7.5\times 10^{-4}\,m\)
Answer & Solution
Correct Answer
(D) \(7.5\times 10^{-4}\,m\)
Step-by-step Solution
Detailed explanation
\({{\text{k}}_{\text{e}}} = \frac{{{{\text{p}}^2}}}{{2{{\text{M}}_{\text{e}}}}} = 500\,{\text{e}} \ldots ({\text{i}})\) \(\ \,{\text{R}} = \frac{{\text{p}}}{{{\text{eB}}}} = \frac{{1000{{\text{m}}_{\text{e}}}{\text{e}}}}{{{\text{eB}}}}\)…
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