Question
Calculate the number of photons emitted per second by a transmitter of 10 kW power, emitting radio waves of wavelength 500 m.




None of these
medium
Solution
The electromagnetic energy radiated by the transmitter is given by
Let n be the number of photons emitted per second by the transmitter. Since the energy of each photons is hv, we have
.
Thus, the number of photons emitted per second in a radio beam is enormously large. Correspondingly, the energy of a ratiophoton is exceedingly small . Hence, ratio engineers do not worry about photons and treat the energy of a ratio wave as continuous.
SIMILAR QUESTIONS
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