Q. The minimum$\ $wavelength of $X$-rays produced in a coolidge tube operated at potential difference of $40\ kV$ is
A) $0.31\ \mathring{\mathrm{A}}$
B) $3.1\ \mathring{\mathrm{A}}$
C) $31\ \mathring{\mathrm{A}}$
D) $311\ \mathring{\mathrm{A}}$
Explanation
(a) $\lambda_{\min} = \frac{12375}{40 \times 10^{3}} = 0.309\ \mathring{\mathrm{A}} \approx 0.31\ \mathring{\mathrm{A}}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.