JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
A light beam is described by \(E=800 \sin \omega\left(t-\frac{x}{c}\right)\) An electron is allowed to move normal to the propagation of light beam with a speed of \(3 \times 10^{7}\;{ms}^{-1}\). What is the maximum magnetic force exerted on the electron ?
- A \(1.28 \times 10^{-18}\, {N}\)
- B \(1.28 \times 10^{-21}\, {N}\)
- C \(12.8 \times 10^{-17} \,{N}\)
- D \(12.8 \times 10^{-18} \,{N}\)
Answer & Solution
Correct Answer
(D) \(12.8 \times 10^{-18} \,{N}\)
Step-by-step Solution
Detailed explanation
\(\frac{{E}_{0}}{{C}}={B}_{0}\) \({F}_{\max }={eB}_{0} {V}\) \(=1.6 \times 10^{-19} \times \frac{800}{3 \times 10^{8}} \times 3 \times 10^{7}\) \(=12.8 \times 10^{-18}\, {N}\)
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