Question 28: EM waves

Question

For plane electromagnetic waves propagating in the z direction, which one of the following  combination  gives the correct possible direction for  $$\overrightarrow E $$ and $$\overrightarrow B $$ field respectively ?

Accepted Answer

Since $\vec{E}$ and $\vec{B}$ are mutually perpendicular. Therefore,
$$
\begin{gathered}
\vec{E} 	imes \vec{B}=\vec{c}=c \hat{k} \\
\Rightarrow(-2 \hat{i}-3 \hat{j}) \cdot(3 \hat{i}-2 \hat{j})=-6+6=0 \\
\Rightarrow(-2 \hat{i}-3 \hat{j}) 	imes(3 \hat{i}-2 \hat{j})=(6+9) \hat{k}=15 \hat{k}
\end{gathered}
$$

Answer

$$\left( {\widehat i + 2\widehat j} \right)\,\,$$ and  $$\left( {2\widehat i - \widehat j} \right)$$

Answer

$$\left(-\, {2\widehat i - 3\widehat j} \right)$$ and $$\left( {3\widehat i - 2\widehat j} \right)$$

Answer

$$\left( {2\widehat i + 3\widehat j} \right)$$ and $$\left( {\widehat i + 2\widehat j} \right)$$

Answer

$$\left( {3\widehat i + 4\widehat j} \right)$$ and $$\left( {4\widehat i - 3\widehat j} \right)$$

EM waves

For plane electromagnetic waves propagating in the z direction, which one of the following combination gives the correct possible direction for $\overrightarrow E and \overrightarrow B $ field respectively ?

Choose the correct answer: