The flux or power of radiated light is proportional to the electric field squared, ie. f e2 where k' + ik" is if there is absorption of this radiation in a medium, then the wavenumber k complex. show that in this case the time averaged flux is given by f=foe xp (-2° . i where the averaging is done over a time period much longer than the period of the oscillation. what must be the sign of k"? explain in words, and with a drawing, what k" > 0 implies for what happens to the flux of radiation as it propagates through an absorbing medium.