Question

(a) An X-ray tube produces a continuous spectrum of radiation with its short wavelength end at 0.45 . 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?

Answer 1

(a) $\lambda =0.45\times {10}^{-10}m$

maximum energy is $E=hc/\lambda =27.6\times {10}^{3}eV=27.6keV$

(b) Accelerating voltage provides energy to the electrons for producing X-rays. To get a X-rays of 27.6 keV, the incident electrons must possess at least $27.6keV$ of kinetic electric energy. Hence, an accelerating voltage of the order of 30 keV is required for producing X-rays.