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प्रश्न
One of the following wavelengths is absent and the rest are present in the X-rays coming from a Coolidge tube. Which one is the absent wavelength?
विकल्प
25 pm
50 pm
75 pm
100 pm
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उत्तर
25 pm
Cutoff wavelength (minimum) is absent in the X-rays coming from a Coolidge tube. Hence, the 25 pm wavelength is absent.
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