Consider an electromagnetic wave propagating in vacuum . Choose t… - Vidyadip

MCQ

Consider an electromagnetic wave propagating in vacuum . Choose the correct statement

A
For an electromagnetic wave propagating in $+y$ direction the electric field is $\vec E = \frac{1}{{\sqrt 2 }}\,{E_{yz}}\,\left( {x,t} \right)\,\hat z$ and the magnetic field is $\vec B = \frac{1}{{\sqrt 2 }}\,{B_z}\,\left( {x,t} \right)\hat y$
B
For an electromagnetic wave propagating in $+y$ direction the electric field is $\vec E = \frac{1}{{\sqrt 2 }}\,{E_{yz}}\,\left( {x,t} \right)\,\hat y$ and the magnetic field is $\vec B = \frac{1}{{\sqrt 2 }}\,B_{yz}\,\left( {x,t} \right)\hat z$
C
For an electromagnetic wave propagating in $+x$ direction the electric field is $\vec E = \frac{1}{{\sqrt 2 }}\,{E_{yz}}\,\left( {y,z,t} \right)\,\left( {\hat y + \hat z} \right)$ and the magnetic field is $\vec B = \frac{1}{{\sqrt 2 }}\,B_{yz}\,\left( {y,z,t} \right)\,\left( {\hat y + \hat z} \right)$
✓
For an electromagnetic wave propagating in $+x$ direction the electric field is $\vec E = \frac{1}{{\sqrt 2 }}\,{E_{yz}}\,\left( {x,t} \right)\,\left( {\hat y - \hat z} \right)$ and the magnetic field is $\vec B = \frac{1}{{\sqrt 2 }}\,B_{yz}\,\left( {x,t} \right)\,\left( {\hat y + \hat z} \right)$

✓

Answer

Correct option: D.

For an electromagnetic wave propagating in $+x$ direction the electric field is $\vec E = \frac{1}{{\sqrt 2 }}\,{E_{yz}}\,\left( {x,t} \right)\,\left( {\hat y - \hat z} \right)$ and the magnetic field is $\vec B = \frac{1}{{\sqrt 2 }}\,B_{yz}\,\left( {x,t} \right)\,\left( {\hat y + \hat z} \right)$

d
Wave in $X-$ direction means $E$ and $B$ should be function of $x$ and $t$

$\overset\frown{y}-\overset\frown{z}\,\bot \,\overset\frown{y}+\overset\frown{z}\,$

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