Match the following types of waves with their wavelength ranges:

$i$. Microwave	$(a)$. $700 \ nm$ to $400 \ nm$
$ii$. Visible light	$(b)$. $1 \ nm$ to $10^{-3} \ nm$
$iii$. Ultraviolet	$(c)$. $0.1 \ m$ to $1 \ mm$
$iv$. $X$-rays	$(d)$. $400 \ nm$ to $1 \ nm$

The terminology of different parts of the electromagnetic spectrum is given in the text. Use the formula $E = hv$ (for energy of a quantum of radiation: photon) and obtain the photon energy in units of $eV$ for different parts of the electromagnetic spectrum. In what way are the different scales of photon energies that you obtain related to the sources of electromagnetic radiation?

Which of the following can be used in cancer treatment?

If a source of power $4 \ kW$ produces $10^{20}$ photons/second,the radiation belongs to a part of the spectrum called

Which of the following electromagnetic waves have the minimum frequency?

Match the electromagnetic radiations given in List-$I$ with their uses given in List-$II$.
| List-$I$ | List-$II$ |
| :--- | :--- |
| $A$) $X$-rays | $P$) Remote switches |
| $B$) $UV$-rays | $Q$) Finger prints in forensic labs |
| $C$) Radio waves | $R$) Crystal structure study |
| $D$) $IR$-rays | $S$) $TV$ communication system |