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(a) An X-ray tube produces a continuous ...

(a) An X-ray tube produces a continuous spectrum of radiation with its short wavelength end at `0.45 Å`. What is the maximum energy of a photon in the radiation?
(b) From your answer to (a), guess what order of accelerating voltage (for electrons) is required in such a tube ?

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(a) 27.6 keV
(b) of the order of 30 kV
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