JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
A linearly polarized electromagnetic wave in vacuum is \(E=3.1 \cos \left[(1.8) z-\left(5.4 \times 10^{6}\right) {t}\right] \hat{\text { i }}\, {N} / {C}\) is incident normally on a perfectly reflecting wall at \(z=a\). Choose the correct option
- A The wavelength is \(5.4\, {m}\)
- B The frequency of electromagnetic wave is \(54 \times 10^{4}\, {Hz}\).
- C The transmitted wave will be \(3.1 \cos \left[(1.8) z-\left(5.4 \times 10^{6}\right) {t}\right] \hat{i}\, {N} / {C}\)
- D The reflected wave will be \(3.1 \cos \left[(1.8) {z}+\left(5.4 \times 10^{6}\right) {t}\right] \hat{{i}}\, {N} / {C}\)
Answer & Solution
Correct Answer
(D) The reflected wave will be \(3.1 \cos \left[(1.8) {z}+\left(5.4 \times 10^{6}\right) {t}\right] \hat{{i}}\, {N} / {C}\)
Step-by-step Solution
Detailed explanation
Reflected wave will have direction opposite to incident wave.
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