Units and their Conversion

What are units?

Units are standards for the measurement of physical quantities. We know Physical quantities are those properties of a substance that can be measured or observed without changing the identity or composition of the substance.

There are seven fundamental physical quantities:

Fundamental physical quantities	S.I. unit	Symbol
1. Length	meter	m
2. Mass	kilogram	kg
3. Time	second	s
4. Temperature	kelvin	K
5. Amount of substance	mole	mol
6. Electric Current	ampere	A
7. Luminous intensity	candela	cd

Fundamental physical quantity

There are several other physical quantities that are derived from fundamental physical quantities and are known as “derived physical quantities”. For example Area, Volume, Pressure, etc.

Let us look at conversion of units of Physical quantities that are used frequently in Chemistry and Physics numerical problems.

This video covers the conversion of units of:

Length
Mass
Volume
Pressure

So, we have learned the conversion of units very well. Here are conversion tables listed for different units and their conversion:

Unit Conversion of Length
1 kilometer	$10^3$ meters
1 centimeter	$10^{-2}$ meter
1 millimeter	$10^{-3}$ meter
1 micrometer	$10^{-6}$ meter
1 nanometer	$10^{-9}$ meter
1 angstrom	$10^{-10}$ meter
1 picometer	$10^{-12}$ meter
1 fermi	$10^{-15}$ meter