Question

Electrons with energy `80 keV` are incident on the tungsten target of an X - rays tube , k- shell electrons of tungsten have `72.5 keV` energy X- rays emitted by the tube contain only

Answer 1

Correct Answer - A::B::C::D
Minimum wavelength of continuous X-ray spectrun is given by `lambda_(min) (in Å)`
`=(12375 )/(E(in eV)`
Here, E = energy of incident electrons (in eV)
=energy corresponding to minimum wavelength `lambda_(min)` of X -ray
`E = 80ke V = 80xx10^3 eV`
`:. lambda_(min) (in Å) = (12375)/(80xx10^3) ~~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 V). Therefore, characteristic X-ray spectrum will also be obtained
because energy of incident electron is high enough out the electron form K or L-shells. `:.` The correct option is (d).