For a plane electromagnetic wave propagating | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The direction of propagation of an electromagnetic wave is given by the direction of the Poynting vector,which is $\vec{E} 	imes \vec{B}$.Given t

Vedclass · Accepted Answer

$-\hat{j}+\hat{k}, -\hat{j}-\hat{k}$

Vedclass · Answer

(B) The direction of propagation of an electromagnetic wave is given by the direction of the Poynting vector,which is $\vec{E} 	imes \vec{B}$.Given the wave propagates in the $x$-direction,we must have $\vec{E} 	imes \vec{B} = \hat{i}$.Let us check option $B$: $\vec{E} = -\hat{j} + \hat{k}$ and $\vec{B} = -\hat{j} - \hat{k}$.Calculating the cross product: $(-\hat{j} + \hat{k}) 	imes (-\hat{j} - \hat{k}) = (-\hat{j} 	imes -\hat{j}) - (\hat{j} 	imes -\hat{k}) + (\hat{k} 	imes -\hat{j}) - (\hat{k} 	imes -\hat{k})$.$= 0 + (\hat{j} 	imes \hat{k}) - (\hat{k} 	imes \hat{j}) - 0 = \hat{i} - (-\hat{i}) = 2\hat{i}$.Since the resulting vector is in the $x$-direction,option $B$ is correct.

For a plane electromagnetic wave propagating in the $x$-direction,which one of the following combinations gives the correct possible directions for the electric field $(E)$ and magnetic field $(B)$ respectively?

Similar Questions

If the magnetic field in a plane electromagnetic wave is given by $\overrightarrow{B} = 3 \times 10^{-8} \sin (1.6 \times 10^{3} x + 48 \times 10^{10} t) \hat{j} \; T$,then what will be the expression for the electric field?

$A$ point source of electromagnetic radiation has an average power output of $800 \, W$. The maximum value of the electric field at a distance $4.0 \, m$ from the source is .... $V/m$.

Atmospheric conditions affect ......... space waves.

Select the correct statement from the following:

Vedclass Test Series

Exam Paper Generator

Online Exam Module