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An electromagnetic wave is propagating in free space in the Z-direction. If the electric field is given by $$E = \cos \left( {\omega t - kz} \right){\bf{\hat i}},$$    where $$\omega t = ck,$$  then the magnetic field is given by

An electromagnetic wave is propagating in free space in the Z-direction. If the electric field is given by $$E = \cos \left( {\omega t - kz} \right){\bf{\hat i}},$$    where $$\omega t = ck,$$  then the magnetic field is given by Correct Answer $$\overrightarrow {\bf{B}} = \frac{1}{c}\cos \left( {\omega t - kz} \right){\bf{\hat j}}$$

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