MCQ
When a beam of accelerated electrons hits a target, a continuous $X-$ ray spectrum is emitted from the target. Which of the following wavelength is absent in the $X-$ ray spectrum, if the $X-$ ray tube is operating at $40,000$ volts........$\mathop A\limits^o $
  • $0.25 $
  • B
    $0.5 $
  • C
    $1.5 $
  • D
    $1$

Answer

Correct option: A.
$0.25 $
a
(a) ${\lambda _{\min }} = \frac{{12375}}{{40,000}} = 0.30\,{Å}$ Hence wavelength less than $0.30 Å$ is not possible.

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