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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 ...
Describe how experiments with X-rays confirm the particle **nature** of **radiation** ...
Here the **photon's energy** Ef is the same as that of **a light quantum** of ... The **wave**
**relation** that connects frequency f with wavelength λ and speed c ...

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NUREG/CR-5550 "Passive Nondestructive Assay of Nuclear ...

Michael **C**. Miller (Chapter **10**) ... 5.1.**6** Determination of **Peak** Position by the First
Moment Method 105 ... 7.3.1 One-Component Example (Uranium **Metal**) ...
**electrons**. The colors of the **emitted light** are characteristic of. the radiating
elements ... The **electron** volt (**eV**) is a unit of energy equal to the **kinetic energy**
gained by an ...

For more information, see NUREG/CR-5550 "Passive Nondestructive Assay of Nuclear ...

Given that

Caesium metal work function = 2.14 eV

Incident light frequency \upsilon = 6*10^{14} Hz.

a) Maximum kinetic energy of the emitted electrons

Photon's energy = energy needed for the emission of an electron (work function) + Maximum kinetic energy of the electron

E = W + K.E

K.E = h \upsilon - W

E = \frac{ 6.63 * 10^{-34} * 6*10^{14}}{1.6*10^{-19}} - 2.14 eV

K.E = 2.485 - 2.140

K.E = 0.345 eV

Hence, Maximum kinetic energy of the emitted electrons K.E = 0.345 eV

b) Stopping potential

By conservation of energy, kinetic energy has to be equal to the change in potential energy.

K.E = eV

V = \frac{K.E}{e}

V = \frac{0.345 eV}{1.6*10^{-19}} = \frac{0.345 * 1.6*10^{-19} V}{1.6*10^{-19}}

V = 0.345 V

c) Maximum speed of the emitted photoelectrons?

Mass of the electron m = 9.1*10^{-31}

Kinetic energy K.E = \frac{1}{2} mv^2

v^2 = \frac{2K.E}{m}

v^2 = \frac{2*0.345 eV}{9.1*10^{-31}}

v^2 = \frac{2*0.345 * 6.1*10^{-19}}{9.1*10^{-31}}

v = \sqrt{\frac{2*0.345 * 6.1*10^{-19}}{9.1*10^{-31}}}

v = 3.323 * 10^{5} m/s

v = 332.3 km/s

Hence, Maximum speed of the emitted photoelectrons v = 332.3 km/s