Science

Science Skills
Introduction to the Metric System
Lesson 1.2

How often do you use the metric system?

The Metric System

The metric system is a more convenient measurement system than the English system used by most people in the United States. It only seems harder because it is not widely used. However, you are exposed to measurements in the metric system every day.

Using the metric system will seem much easier if you are able to use it to make estimations. You are familiar with estimating measurements based on English units such as inches, miles, cups, and pounds. It is just as easy with the metric system!

Use Your Body As a Metric Ruler

In the metric system, all units of length are based on the meter. Metric rulers will have lines indicating millimeters (mm), which are equal to 1/1000 of 1 meter.

10 millimeters = 1 centimeter (cm)
100 millimeters = 1 decimeter
1000 millimeters = 1 meter

Use a ruler to make the following measurements:

hand span (measure your outstretched hand between tip of thumb and tip of little finger)	______ centimeters
width of thumb just below the nail	______ centimeters
width of the back my hand	______ centimeters

Now use your built-in ruler to measure the size of objects.

What is the width of your computer screen?
What is the length of a pen?

How did the estimate of length using your body ruler compare to an actual measurement? Record your data in your e-journal.

Other common references to estimate metric measurements are:

height of a doorknob from the floor:

1 meter

thickness of a dime

1 millimeter

mass of a paper clip

1 gram

mass of 100 pennies

250 grams

width of a CD-ROM

120 millimeters

width of a floppy disk

90 millimeters

mass of one liter of water

1 kilogram

mass of a pickup truck

1000 kilograms