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Question
The Kβ X-ray of argon has a wavelength of 0.36 nm. The minimum energy needed to ionize an argon atom is 16 eV. Find the energy needed to knock out an electron from the K shell of an argon atom.
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Solution
Given:-
Wavelength of Kβ X-ray of argon, λ = 0.36 nm
Energy needed to ionise an argon atom = 16 eV
Energy of Kβ X-ray of argon (E) is given by
`E = 1242/0.36 = 3450 "eV"`
Energy needed to knock out an electron from K shell
EK = (3450 + 16) eV
EK = 3466 eV ≈ 3.47 keV
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