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प्रश्न
The X-ray beam emerging from an X-ray tube
विकल्प
is monochromatic
has all wavelengths smaller than a certain maximum wavelength
has all wavelengths greater than a certain minimum wavelength
has all wavelengths lying between a minimum and a maximum wavelength
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उत्तर
has all wavelengths greater than a certain minimum wavelength
The X-ray beam emerging from an X-ray tube consists of wavelengths greater than a certain minimum wavelength called cutoff wavelength.
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