Long and Short - Centimeters and Meters

Length tells us how long an object is from one end to the other. Imagine a straight line stretching between two points; the measurement of that line is the length.

Centimeter ($cm$) is a small unit of length used for short objects. Look at a standard school ruler; the distance between two big numbers like $0$ and $1$ is exactly $1\text{ cm}$. We use it to measure things like a pencil, a sharpener, or a finger.

Meter ($m$) is a bigger unit of length used for longer objects. $1$ meter is exactly equal to $100$ centimeters. Imagine a long tailor's tape or the height of a standard doorknob from the floor to visualize $1\text{ meter}$.

To measure an object using a ruler, you must place one end of the object exactly at the '$0$' mark. Do not start from the very edge of the ruler, as there is usually a small gap before the '$0$' mark. The number where the object ends is its length.

Choosing the right unit is important for measurement. For example, the length of a classroom or a saree should be measured in meters ($m$), while the length of a notebook or a spoon should be measured in centimeters ($cm$).

Standard units like meters and centimeters are used so that everyone gets the same measurement. Non-standard units like handspans, footsteps, or arm-lengths change from person to person and are not accurate for official work.

Conversion between units helps in comparing lengths. Since $1\text{ m} = 100\text{ cm}$, a cloth that is $2\text{ m}$ long is the same as $200\text{ cm}$ ($100 + 100$).

Kilometer ($km$) is used for very long distances, such as the distance between your home and your school or the distance between two cities. $1\text{ kilometer}$ is equal to $1000\text{ meters}$.