Question

Match the column I with column II:

Column 1	Column 2
(A) Distance between earth and sun	(p) Micron
(B) Interatomic distance in a solid	(q)Fermi
(C) Size of a nucleus	(r) Light year
(D) Wavelength of infrared laser	(s) Angstrom

(A) A – p, B – q, C – r, D – s
(B) A – r, B – s, C – q, D – p
(C) A – q, B – p, C – s, D – r
(D) A – s, B – r, C – p, D – q

Answer 1

Micron: - micron is used to measure particle size. It is short form for one micrometre, or one-millionth of a meter.
Fermi: - The Fermi is an SI unit of length equal to ${{10}^{-15}}$ metres, which means a quadrillionth of one. It is also known as femtometre.
Light year: - 1 light year is the distance that light travels in one year, about $9\cdot 4607\times {{10}^{12}}\text{ km}$ .
Angstrom: - The angstrom is a metric unit of length equal to ${{10}^{-10}}$ m. Its symbol is Å,

Complete step by step answer
(A) As the distance between earth and sun is very large i.e. $148\cdot 69$ million km and light year is the distance of the unit that was used to measure the astronomical distances therefore the correct match for option (A) is (r) light year.
(B) Interatomic distance in solid refers to the distance between the nuclei of atoms in a material. As it is of order of ${{10}^{-10}}$ meters. Therefore, (s) angstrom (Å) is the correct option (as $1\text{A}{}^\circ \text{=1}{{\text{0}}^{-10}}$ m).
(C) The order of size of the nucleus is ${{10}^{-15}}$ meters. Thus, the correct option is (q) Fermi, as 1 Fermi $={{10}^{-15}}$ metres.
(D) Wavelength of infrared laser lies in the range between 1,000 micrometres (µm) and 760 nanometres.
Thus option (B) micron is the correct answer.

Note
Learn the following prefixes frequently used in the metric system.

Symbol	Name	Factor	Symbol	Name	Factor
Y	Yotta	${{10}^{24}}$	y	yokto	${{10}^{-24}}$
Z	Zetta	${{10}^{21}}$	z	zepto	${{10}^{-21}}$
E	Exa	${{10}^{18}}$	a	atto	${{10}^{-18}}$
P	Peta	${{10}^{15}}$	f	femto	${{10}^{-15}}$
T	Tera	${{10}^{12}}$	p	pico	${{10}^{-12}}$
G	Giga	${{10}^{9}}$	n	nano	${{10}^{-9}}$
M	Mega	${{10}^{6}}$	µ	micro	${{10}^{-6}}$
k	Kilo	${{10}^{3}}$	m	milli	${{10}^{-3}}$
h	Hector	${{10}^{2}}$	c	centi	${{10}^{-2}}$
da	Deca	${{10}^{1}}$	d	deci	${{10}^{-1}}$