The Total solution for NCERT class 6-12
(a) An X-ray tubeproduces a continuous spectrum of radiation with its short wavelength end at0.45 Å. What is the maximum energy of a photon in the radiation?
(b) Fromyour answer to (a), guess what order of accelerating voltage (for electrons) isrequired in such a tube?
(a) Wavelengthproduced by an X-ray tube,
Planck’s constant, h =6.626 × 10−34 Js
Speed of light, c = 3 × 108 m/s
The maximum energy of aphoton is given as:
Therefore, the maximumenergy of an X-ray photon is 27.6 keV.
(b) Accelerating voltage provides energy to theelectrons for producing X-rays. To get an X-ray of 27.6 keV, the incidentelectrons must possess at least 27.6 keV of kinetic electric energy. Hence, anaccelerating voltage of the order of 30 keV is required for producing X-rays.