NTA Abhyas JEE Main2020PhysicsAtomic PhysicsPractice
Electrons with energy 80 keV are incident on the tungsten target of an X-ray tube. K-shell electrons of tungsten have 72 . 5 keV energy. X-rays emitted by the tube contain only
Options
- AA continuous X-ray spectrum (Bremsstrahlung) with a minimum wavelength of 0.155 Å
- BA continuous X-ray spectrum (Bremsstrahlung) with all wavelengths
- CThe characteristic X-ray spectrum of tungsten
- DA continuous X-ray spectrum (Bremsstrahlung) with a minimum wavelength of0.155 Å and the characteristic X-ray
Correct answer
D. A continuous X-ray spectrum (Bremsstrahlung) with a minimum wavelength of0.155 Å and the characteristic X-ray
Step-by-step solution
Minimum wavelength of continuous X - ray spectrum is given by λ min (in Å) = 12375 E Here E = energy of incident electrons (in eV) = energy corresponding to minimum wavelength E = 80 keV = 80 x 10 3 eV Therefore, λmin (ni Å)= 12375 80 × 1 0 3 = 0.155 Also, the energy of the incident electrons (80 keV) is more than the ionization energy of the K - shell electrons (i. e., 72. 5 keV), Therefore, characteristic X-ray spectrum will also be obtained because the energy of the incident electr