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

What are called heat waves?

Light of wavelength $1 \,nm$ belongs to the following class of waves:

The waves used in telecommunication are

The electromagnetic waves with wavelengths $10^7 \ m$,$10^{-10} \ m$,and $10^{-7} \ m$ belong to which categories respectively?

Arrange the following in the ascending order of wavelength $(\lambda) :$
$(A)$ Microwaves $(\lambda_1)$
$(B)$ Ultraviolet rays $(\lambda_2)$
$(C)$ Infrared rays $(\lambda_3)$
$(D)$ $X-$rays $(\lambda_4)$
Choose the most appropriate answer from the options given below $:-$