How Big Are Millimeters? A Kid-Friendly Guide

If you’ve ever looked closely at a ruler or tape measure, you might have noticed some tiny lines that are too small to count. Those lines are marking millimeters, a unit of measurement that is smaller than a centimeter and bigger than a micrometer. In this article, we’ll explore the world of millimeters and learn just how big (or small) they are.

What are Millimeters?

Millimeters (mm) are a unit of length in the metric system, which is used in most countries around the world. They are one-thousandth of a meter, which means that you would need 1,000 millimeters to make up one meter. To give you an idea of how small a millimeter is, it’s about the width of a pinhead or the thickness of a credit card!

Comparing Millimeters to Other Units of Measurement

To understand just how big (or small) millimeters are, let’s compare them to some other units of measurement.

• Centimeters: One centimeter is equal to 10 millimeters. So, if you have a ruler that measures in centimeters, each centimeter will have 10 millimeters.
• Meters: One meter is equal to 1,000 millimeters. That means if you have a meter stick, it will have 1,000 millimeters on it.
• Inches: One inch is equal to 25.4 millimeters. So, if you have a ruler that measures in inches, each inch will have 25.4 millimeters.

Fun Facts About Millimeters

• The thickness of a CD or DVD is about 1.2 millimeters.
• The diameter of a dime is about 18 millimeters.
• A human hair is about 100 micrometers, which is 0.1 millimeters.
• The thickness of a piece of paper is about 0.1 millimeters.

Conclusion

Millimeters may be small, but they play a big role in our lives. We use them to measure all sorts of things, from the length of a pencil to the size of a building. Now that you know how big (or small) a millimeter is, you can start exploring the world of measurement and see just how much there is to discover!

In summary, millimeters are a unit of length in the metric system that are one-thousandth of a meter. They are smaller than centimeters and larger than micrometers. With this kid-friendly guide from Khan Academy, you can explore the world of millimeters and learn some fun facts about this important unit of measurement.