Infrared radiations are detected by:

The electromagnetic waves of frequency $2 \ MHz$ to $30 \ MHz$ are used in:

To which region of the electromagnetic spectrum does the frequency $1\, GHz$ correspond?

Match the List-$I$ (Phenomenon associated with electromagnetic radiation) with List-$II$ (Part of electromagnetic spectrum) and select the correct code from the choices given below:

List-$I$	List-$II$
$I$. Doublet of sodium	$A$. Visible radiation
$II$. Wavelength corresponding to temperature associated with the isotropic radiation filling all space	$B$. Microwave
$III$. Wavelength emitted by atomic hydrogen in interstellar space	$C$. Short radio wave
$IV$. Wavelength of radiation arising from two close energy levels in hydrogen	$D$. $X$-rays

Write the sources of visible rays and ultraviolet rays and their uses.

List-$I$	List-$II$
$A$. $UV$ rays	$(i)$ Diagnostic tool in medicine
$B$. $X-$rays	$(ii)$ Water purification
$C$. Microwave	$(iii)$ Communication,Radar
$D$. Infrared wave	$(iv)$ Improving visibility in foggy days

Choose the correct answer from the options given below.