Question
Suppose that the electric field part of an electromagnetic wave in vacuum is E = {(3.1 N/C) cos [(1.8 rad/m) y + (5.4 × 106 rad/s)t]} Write an expression for the magnetic field part of the wave.
Solution
Electric field E = {(3.1 N/C) cos [(1.8 rad/m) y + (5.4 × 106 rad/s)t]
Expression of magnetic field part of the wave
E is along and c is along ,
c is the direction of
Clearly B is in the direction of and
Thus,
is completely represented as,