JEE Advance - Physics (2008 - Paper 1 Offline - No. 3)
Which one of the following statements is WRONG in the context of X-rays generated from a X-ray tube?
Wavelength of characteristic X-rays decreases when the atomic number of the target increases.
Cut-off wavelength of the continuous X-rays depends on the atomic number of the target.
Intensity of the characteristic X-rays depends on the electrical power given to the X-ray tube.
Cut-off wavelength of the continuous X-rays depends on the energy of the electrons in the X-ray tube.
Explanation
The cut-off wavelength is given by $${\lambda _{\min }} = {{hc} \over {eV}}$$
The cut-off wavelength depends on the energy eV of the accelerated electrons and is independent of the atomic number of target. Thus, greater the accelerating voltage for electrons, higher will be kinetic energy it attains before striking the target, higher will be the frequency of X-rays and smaller will be wavelength.
Comments (0)
