Question

The voltage to be applied to an X-ray tube to produce X-rays of wavelength of 1$A^0$ (h$=6.63\times {10}^{-34}$Js and $c=3\times {10}^8$ m/s)

• A. $12.38\times {10}^{3}V$
• B. $11.42\times {10}^{3}V$
• C. $3.2\times {10}^{3}V$
• D. $1.67\times {10}^{3}V$

Answer 1

The correct option is A $12.38\times {10}^{3}V$

$\lambda =1A^{\circ }=1\times {10}^{-10}m$
$p.d.\times e=energy=\frac{hc}{\lambda }$
$p.d.=\frac{hc}{\lambda e}$
$=\frac{6.63\times {10}^{-34}\times 3\times {10}^8}{1\times 10{\times }^{-10}\times 1.6\times {10}^{-19}}$
$=12.43\times {10}^{3}V$

So, the answer is option (A).