question_answer 21)

                         An EM wave radiates outwards from a dipole antenna, with E0 as the amplitude of its electric field vector. The electric field E0 which transports significant energy from the source falls off as                                 (a)                                    (b)  (c)                                   (d) remains constant

Answer:

  (c)From a diode antenna, the em waves are radiated outwards. The amplitude of electric field vector (E0) which transports significant energy from the source falls off intensity inversely as the distance (r) from the antenna, i.e., .