A beam of electrons striking a cooper target produces X-rays. Its spectrum is as shown. Keeping the voltage same if the copper target is replaced with a different metal, the cut-off wavelength and characteristic lines of the new spectrum will change in comparison with old as:

Options

A. cut-off wavelength will remain unchanged while characteristic lines will be different.
B. Both cut-off wavelength and characteristic lines will remain unchanged.
C. Both Cut-off wavelength and characteristic lines will be different
D. Cut-off wavelength will be different while characteristic lines will remain unchanged

Answer

A

Explanation

Cut-off wave length depend on accelerating voltage and characteristic wavelength depends on nature of the target material.