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प्रश्न
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.
उत्तर
(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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