Calculate The Number Of Photons Emitted Per Second By A Transmitter Of 10 KW Power, Emitting Radio Waves Of Wavelength 500 M. 

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Question

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

Solution

Correct option is

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 ratio-photon 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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Q2

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Q3

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In an accelerator experiment on high-energy collisions of the electrons with positrons, a certain event is interpreted as the annihilation of an electron-positron pair of total energy 10.2 BeV into two -rays of equal energy. Find the wavelength associated with each -ray. 

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Q9

 

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

Q10

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