Question

An electromagnetic radiation has an energy of 13.2 KeV. Then the radiation belongs to the region of

• A. Ultraviolet light
• B. Visible light
• C. Infrared
• D. X-ray

Answer 1

Answer: (D)

As we already know that Energy of electromagnetic radiation depends upon the frequency of radiation.

Energy of a photon of $EM$ radiation with frequency is $E=h\nu$

Frequency and wave length are related by $\lambda \nu =c$

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

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

$=\frac{1240ev-nm}{13.2kev}$

$=\frac{1240ev-nm}{13.2\times 1000ev}$

$=\frac{1240}{13200}=0.093nm$

$=0.093nm$

As $X-ray$ wavelength is in the Range of $0.01nm$ to $1nm$.

Hence answer is X-rays.