Understanding Metric Length and SI Units

The metric system can be defined as a system of measurement that uses the litre, metre, and gram as base units of metric length (distance), capacity (volume), and weight (mass) respectively.

To measure larger or smaller quantities, we use units derived from the metric units.

• The units to the right of the base are lesser than the base unit. As we move to the right, each unit is ten times smaller or one-tenth of the unit to its left. So, the word ‘deci’ means one-tenth of the base unit, ‘centi’ is one-tenth of ‘deci’ or one-hundredth of the base unit and ‘milli’ is one-tenth of ‘centi’ or one-thousandth of the base unit.

• The units to the left of the base unit are larger than the base unit. As we move to the left side, each unit is 10 times greater than the unit to its right side. So, a ‘deca’ means 10 times of the base unit, ‘hecto’ is ten times of ‘deca’ or hundred times of the base unit and ‘killo’ is ten times of ‘hecto’ or thousand times of the base unit.

So, the units for metric length, capacity(volume), and  weight (mass) in the metric system are:

Metric Length: Centimeter (cm), Millimeter (mm), Meter (m), Decimeter (dm), and Kilometer (km) are used to measure how wide or long, or tall an object is.

What is the SI Unit of Metric Length?

In the metric system, the SI unit of length is a meter which is defined as follows:

“The metric length of the path that is travelled by light in a vaccum within 1⁄299792458 seconds”.

Some of the other units also include:

• Kilometres

• Nanometer

• Millimetres

• Centimetres

• Meters

• Decimeters

For understanding how big the metric units are, look at the table below:

Other Non-SI Metric Length Units

If we take a look at the Imperial and U.S. customary systems, then the basic unit of metric length is the yard. Some other units include:

• Thou (1⁄1000 of an inch)

• Line (1⁄12 of an inch)

• Inch (25.4 mm)

• Foot (12 inches, 0.3048 m)

Measure of Metric Lengths

Examples include measuring the thickness or metric length of cloth, a debit card, or distance between 2 cities.

Converting Larger Units to Smaller Units

• 1 centimeter = 10 millimeters

• 1 meter = 100 centimeters

• 1 meter = 1,000 millimeters

• 1 kilometer = 1,000 meters

To Convert bigger units to smaller units we multiply the number of large units by the conversion factor for the appropriate smaller units.

The Table Given Below Makes Conversion Easy:

Solved Examples on Unit Conversion

Example 1: Convert 5 km to m.

As 1 km = 1000 m

Therefore, 5 km equals 5 × 1000 equals 5000 m. 

Example 2: How do you Convert m to cm and mm?

In this activity, you will convert between metric units of metric length: kilometres, metres, centimetres, and millimetres.

1 km = 1000 m

1 m = 100 cm

1 m = 1000 mm

1 cm = 10 mm

Why Must Students Know About the Metric System?

The Metric System is important as without it, we would be completely confused about the units. It is completely scientific and has repeatable standards of measurement.  It uses units like meter, litre and gram so as to measure length, liquid, volume and mass. Students will need to know about the Metric System so as to understand all the different concepts that will be applicable in Math and the Science subjects. Having a standard system of measurement is the only way to go when measuring things as that clears all the confusions.

How can Students Make Notes for the Metric System?

• They can go to Vedantu and then look for Metric Length - Explanation, Conversions, SI Unit, Measures, Problems, and FAQs

• Read this carefully and then make notes

• Condense everything that’s on the page by highlighting all the important parts

• Compare what you’ve written with what’s on the page

• Go through everything before the exams

• Avoid skipping anything that’s on the page

Fun Facts