For plane electromagnetic wave propagating in the x-direction, which one of the following combinations gives the correct possible direction for Electric field (E) and Magnetic field (B) respectively?
(1) \(\hat{j}+\hat{k}, \hat{j} + \hat{k}\)
(2) \(-\hat{j}+\hat{k}, -\hat{j} - \hat{k}\)
(3) \(\hat{j}+\hat{k}, -\hat{j} - \hat{k}\)
(4) \(-\hat{j}+\hat{k}, -\hat{j} + \hat{k}\)
Correct answer: (2) \(-\hat{j}+\hat{k}, -\hat{j} - \hat{k}\)
Explanation:
\(\vec{v}|| \vec{E}\times \vec{B}\), \(\hat{v} = \hat{i}\)
Option (1) \(\vec{E}\times \vec{B} = \vec{0}\;(\vec{E}|| \vec{B})\)
Option (2) \(\vec{E}\times \vec{B} = 2\hat{i}\;(\vec{E}|| \vec{B})\)(parallel to \(\vec{i}\))
Option (2) \(\vec{E}\times \vec{B} = \vec{0}\;(\vec{E}|| \vec{B})\)
Option (2) \(\vec{E}\times \vec{B} = \vec{0}\;(\vec{E}|| \vec{B})\)