Question

An X-Ray tube operates at a p.d. of $12400V$. The wavelength of the highest frequency X-Rays emitted by this tube is nearly:($hc=1240eV-nm$)

• A. $12.4A^o$
• B. $1.24A^o$
• C. $2.48A^o$
• D. $1A^o$

Answer 1

The correct option is D $1A^o$

$Energy=p.d\times e$
=$12400V\times e$
$=12400eV$
$Energy=\frac{hc}{\lambda }$
$\lambda =\frac{hc}{energy}$
$=\frac{1240}{12400}nm$
$=0.1nm$
$=1A^0$