Question

1 nm is equal to
(a)1 Å 
(b)${10}^{-3}$ mm
(c)${10}^{-9}$ m
(d)100

Answer 1

Hint: Nanometer is known to be the specific unit of measurement which is used to measure the size of atoms. For example,the value of diameter of the helium atom is found to be 0.06 nm.

Correct answer:
One nanometer is scientifically expressed as 1×${10}^{-9}$ m.
-Nanometer is denoted by nm.
-Nanometer was previously called millimicrometer or millimicron. But this was dropped because it got confusing to many people.
-Nano meter is used to measure the dimensions of atoms. It is also used to measure the wavelength of light. Previously the unit ångström was used to measure the wavelength of light (Å). 1 Å = 0.1 nanometer.
-A nanometer is often used to measure matters that are very small. Atoms and molecules, the smallest portions of the entirety around us, are measured in nanometers. For instance a water molecule is much less than one nanometer. A standard germ is set 1,000 nanometers.
-The name nanometer is the SI unit, it is derived from greek where nano means dwarf.
-Nanometer is one-billionth of a meter.
-Inside of our computer, there are tiny switches present that are known to be only 100 nanometers wide. About 1,000 of these types of switches can easily fit across the width of a single hair.

So the correct answer is ${10}^{-9}$ m.

Note:
Here is a table with a list of factors to measure the length in terms of meter.

Sr.no	Factor	Prefix	Symbol
1	${10}^{-3}$	milli	m
2	${10}^{+3}$	kilo	k
3	${10}^{-6}$	micro	μ
4	${10}^{+6}$	mega	M
5	${10}^{-9}$	nano	n
6	${10}^{+9}$	giga	G
7	${10}^{-12}$	pico	p
8	${10}^{+12}$	tetra	T
9	${10}^{-2}$	centi	c
10	${10}^{+2}$	hecto	h
11	${10}^{-1}$	deci	d