Metric System of Measurement

Let us understand what metric system is

The standard way to calculate dimensions of an object, find its volume or calculate distance, time, and speed of anything is done by measuring quantities in metric units. For example, if we want to measure the distance between your house and your best friend’s house, then we will take a standard unit to do the same. It can be meters, yards, miles, etc.

Most of the quantities present around are measurable if their quantity is small. For example, milk, apples, potatoes, etc., are all measurable quantities by units. Whereas sugar, salt, air, etc., can be measured as a whole. While some quantities, like water in oceans, how many planets are there in the universe, how many stars are there in the galaxy, etc., are non-measurable.

We can calculate the length and breadth of a two-dimensional object. We can calculate the volume of a three-dimensional object by multiplying the area of a two-dimensional object by its length. We can estimate time and distance with respect to the planetary positions on earth. All these units can be measured in a metric system.

Fun fact:

1. International system of units, known as SI units, started implementing the metrication process. These units are followed by almost every country to maintain global understandings of units.
2. The metric units followed in America are known as United States Customary Units (USCS).

Difference between SI units and USCS units

Measurement	SI	USCS
Distance	Metre	Foot, yard, inch
Volume	Litre	Quart, tablespoon, gallon
Mass	Gram	Slug
Force	Newton	Pound, ton, ounce
Time	Second	Second
Electric current	Ampere	Ampere
Energy	Joule	Foot-pound
Temperature	Kelvin or Celsius	Fahrenheit

Length

Length is a quantity used to measure size of an object or a particular distance between various objects. The standard unit to measure length is meter.

Metric conversion of length

kilometer	hectometer	decameter	meter	decimeter	centimeter	millimeter
1000	100	10	1	0.1	0.01	0.001

Example: Convert 20 cm into m.
Solution:
We know, 0.01 m = 1 cm
This implies, 20 cm = 20 x 0.01 = 0.2m

Weight

Weight denotes the mass of an object. Whenever we need to measure the quantity of an object or commodity, we use weight. The SI unit of weight is gram. We can measure weight by using a weight balance or weighing scale.

Metric conversion of weight

kilogram	hectogram	decagram	gram	decigram	centigram	milligram
1000	100	10	1	0.1	0.01	0.001

Example: Convert 20 milligrams into kilograms.

Example: Convert 20 milligrams into kilograms.
Solution:
We know, 1 milligram = 0.001 g
Therefore, 20 milligram = 20 x 0.001 = 0.02 g
Also, 1000 gm = 1 kilogram
Therefore, 0.02 / 1000 = 0.000002 kilogram

Capacity

Capacity denotes the volume of an object. Whenever we want to measure the volume or quantity holding capacity of an object, we need to find its volume. Volume can be found only in three-dimensional objects, like cube, cuboid, prism, etc. For example, the volume of a cube is the product of its length, breadth and height = side3. It is denoted by cm3, m3, etc. The SI unit to measure capacity is litre.