IIT JEE Level Revision Questions - 44. X-Rays

Past JEE Question

To produce charateristic X-rays using a Tungsten target in an X-ray generator, the accelerating voltage should be greater than ________ volts and the energy of the characteristic radiation is __________.
(The binding energy of the innermost electron in tungsten is 40 Kev).(JEE 1983 Screening)

Answer: 40 kV, 40 kV

Revision question 1

Find the maximum potential difference which may be applied across an X-ray tube with tungsten target without emitting any characteristic K or L X-ray.

The energy levels of the tungsten atom with an electron knocked out are as follows:

Cell---------------- Energy
containing---------- in
vacancy-------------keV

K -----------------69.5

L------------------11.3

M------------------ 2.3

(Reference: Problem No. 21 in HC Verma)