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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 ...

For more information, see 6.4: The Compton **Effect** - **Physics** LibreTexts

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.