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6.4: The Compton Effect - Physics LibreTexts

Nov 5, 2020 ... The Compton effect is the term used for an unusual result observed when X-rays are ... Describe how experiments with X-rays confirm the particle nature of radiation ... relativity and the concept of a light quantum, which we now call a photon. ... In Equation 6.4.1, E is the total energy of a particle, p is its linear ...

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Given that

Frequency of monochromatic light f = 6.0* 10^{14} Hz

Power emitted P = 2.0 * 10^{-3} W

a) What is the energy of a photon in the light beam?

            Recall the photon energy equation

                 E = hf   

             Where, E - energy of photons, h -  Planck constant = 6.63* 10^{-34} J and f - frequency of waves

Step 1:  Substituting the known values in the photon energy equation

                Photon energy E = 6.63* 10^{-34} * 6.0* 10^{14}

                                           E = 3.98 * 10^{-19}

                  Thus, energy of the photon E = 3.98 * 10^{-19} J

b) How many photons per second, on an average, are emitted by the source?

        The transmitted (P) power within the light equivalent to (n) times the energy per (E) photon.

                         P = nE

                Where, n - Number of photons released per second by source

Step 1: Set up an equation for number of photons per second,

                   n = \frac{P}{E}

                   n = \frac{2.0 * 10^{-3}}{3.98 * 10^{-19}}

                   n = 5.0 * 10^{15}

              Hence, number of photons per second n = 5.0 * 10^{15} photons per second.