Q. If the potential difference applied across $X$-ray tube is $V$ volts, then approximately minimum wavelength of the emitted $X$-rays will be
A) $\frac{1227}{\sqrt{V}}\mathring{\mathrm{A}}$
B) $\frac{1240}{V}\mathring{\mathrm{A}}$
C) $\frac{2400}{V}\mathring{\mathrm{A}}$
D) $\frac{12400}{V}\mathring{\mathrm{A}}$
Explanation
(d) $\lambda_{\min} = \frac{hc}{eV} = \frac{6.6 \times 10^{- 34} \times 3 \times 10^{8}}{1.6 \times 10^{- 19}V} = \frac{12375}{V} \approx \frac{12400}{V}\mathring{\mathrm{A}}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.