Question

The order of potential difference applied between cathode and anode in an X-ray tube will be

• A. ${10}^{3}V$
• B. ${10}^{2}V$
• C. ${10}^{4}V$
• D. ${10}^{1}V$

Answer 1

The correct option is C ${10}^{4}V$

Approximate range of frequency for X rays is:
$\nu =2\times {10}^{18}Hz$
The energy possessed by this E $=h\nu =1.3\times {10}^{-15}J$
This energy is the energy gained by and electron accelerated by a potential V.
$eV=E$

$V=\frac{E}{e}=\frac{1.3\times {10}^{-15}}{1.6\times {10}^{-19}}=8000V$

as we can see potential is of the order of ${10}^{4}Volts$