Question

The energy of the em waves is of the order of 15 keV. To which part of the spectrum does it belong?

• A. $\gamma$ rays
• B. x rays
• C. Infra - red rays
• D. Ultraviolet rays

Answer 1

Answer: (B)

x rays

$E=\frac{hc}{\lambda }$

or $\lambda =\frac{hc}{E}=\frac{(6.6\times {10}^{-34})\times (3\times {10}^8)}{15\times {10}^3\times 1.6\times {10}^{-19}}=0.8\times {10}^{-10}m=0.8A^o$

So it is nearly related to the X-ray wavelength.