MCQ
The potential difference between the cathode and the target in a Collidge tube is $100 kV$. The minimum wavelength of the $X-$ rays emitted by the tube is
- A$0.66\ Å$
- B$9.38\ Å$
- C$0.246\ Å$
- ✓$0.123\ Å$
✓
Answer
Correct option: D.
$0.123\ Å$
d
(d) ${\lambda _{\min }} = \frac{{hc}}{{eV}} = \frac{{6.6 \times {{10}^{ - 34}} \times 3 \times {{10}^8}}}{{1.6 \times {{10}^{ - 19}} \times 100 \times {{10}^3}}}$
(d) ${\lambda _{\min }} = \frac{{hc}}{{eV}} = \frac{{6.6 \times {{10}^{ - 34}} \times 3 \times {{10}^8}}}{{1.6 \times {{10}^{ - 19}} \times 100 \times {{10}^3}}}$
$ = 0.123{Å}$
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