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Question
Cutoff wavelength of X-rays coming from a Coolidge tube depends on the
(a) target material
(b) accelerating voltage
(c) separation between the target and the filament
(d) temperature of the filament.
Options
target material
accelerating voltage
separation between the target and the filament
temperature of the filament.
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Solution
accelerating voltage
Cutoff wavelength (`lambda_min`) is given by `lambda_min = (hc)/(eV)`
Here,
h = Planck's constant
c = Speed of light
V = Accelerating voltage
e = Charge of electron
Clearly, a cutoff wavelength depends on accelerating voltage. It does not depend on the target material, separation between the target and the temperature of the filament.
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