Question 125: EM waves

Question

A plane electromagnetic wave is propagating
along the direction
${{\widehat i + \widehat j} \over {\sqrt 2 }}$
, with its polarization
along the direction $\widehat k$ . The correct form of the
magnetic field of the wave would be (here B
0
is an appropriate constant) :

Accepted Answer

Direction of propagation = ${{\widehat i + \widehat j} \over {\sqrt 2 }}$
Electric field is in direction = $\widehat k$
As $\overrightarrow E  	imes \overrightarrow B $ = ${{\widehat i + \widehat j} \over {\sqrt 2 }}$
Propagation direction of $\overrightarrow B  = {{\widehat i - \widehat j} \over {\sqrt 2 }}$

Answer

${B_0}{{\widehat i - \widehat j} \over {\sqrt 2 }}\cos \left( {\omega t - k{{\widehat i + \widehat j} \over {\sqrt 2 }}} \right)$

Answer

${B_0}{{\widehat i + \widehat j} \over {\sqrt 2 }}\cos \left( {\omega t - k{{\widehat i + \widehat j} \over {\sqrt 2 }}} \right)$

Answer

${B_0}{{\widehat j - \widehat i} \over {\sqrt 2 }}\cos \left( {\omega t + k{{\widehat i + \widehat j} \over {\sqrt 2 }}} \right)$

Answer

${B_0}\widehat k\cos \left( {\omega t - k{{\widehat i + \widehat j} \over {\sqrt 2 }}} \right)$

EM waves

A plane electromagnetic wave is propagating along the direction {{\widehat i + \widehat j} \over {\sqrt 2 }} , with its polarization along the direction \widehat k . The correct form of the magnetic field of the wave would be (here B 0 is an appropriate constant) :

Choose the correct answer: