The electric field of a plane electromagnetic wave is given by\({\rm{\vec E}} = {{\rm{E}}_0}\widehat {i{\rm{\;}}}{\rm{cos\;}}\left( {{\rm{kz}}} \right){\rm{\;cos\;}}\left( {\omega {\rm{t}}} \right)\) The corresponding magnetic field \(\vec B\) is then given by:

• A. \(\vec B{\rm{\;}} = \frac{{{{\rm{E}}_0}}}{{\rm{C}}}\widehat j{\rm{sin\;}}\left( {{\rm{kz}}} \right)\;{\rm{sin\;}}\left( {\omega {\rm{t}}} \right)\)
• B. \(\vec B{\rm{\;}} = \frac{{{{\rm{E}}_0}}}{{\rm{C}}}\widehat j{\rm{sin\;}}\left( {{\rm{kz}}} \right){\rm{\;cos\;}}\left( {\omega {\rm{t}}} \right)\)
• C. \(\vec B{\rm{\;}} = \frac{{{{\rm{E}}_0}}}{{\rm{C}}}{\rm{\mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\frown$}}\over j} cos\;}}\left( {{\rm{kz}}} \right){\rm{\;sin\;}}\left( {\omega {\rm{t}}} \right)\)
• D. \(\vec B{\rm{\;}} = \frac{{{{\rm{E}}_0}}}{{\rm{C}}}{\rm{\mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\frown$}}\over k} sin\;}}\left( {{\rm{kz}}} \right)\;{\rm{cos\;}}\left( {\omega {\rm{t}}} \right)\)