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 `X` - ray spectrum , if the `X` - ray tube is operating at `40,000 "volts"`?

Options

A. `0.25 Å`
B. `0.5 Å`
C. `1.5 Å`
D. `1.0 Å`

Answer

A

Explanation

`lamda_("min")(Å)=(12375)/V=(12375)/(40000)=0.30Å`
Less than this is not possible.