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Question
The potential difference applied to an X-ray tube is increased. As a result, in the emitted radiation,
(a) the intensity increases
(b) the minimum wavelength increases
(c) the intensity remains unchanged
(d) the minimum wavelength decreases.
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Solution
(c) the intensity remains unchanged
(d) the minimum wavelength decreases
Cutoff wavelength (`λ_min`) is given by
`λ_min = (hc)/(eV)`
Here,
h = Planck's constant
c = Speed of light
V = Accelerating voltage
e = Charge of electron
If the potential difference applied to an X-ray tube (V) is increased, then the minimum wavelength (cutoff wavelength) gets decreased.
Intensity is not affected by the potential difference applied.
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