1. The Metric System: Measuring Length
7th Grade
Earth Science
The Metric System: Measuring Length
Write Everything in Blue!!!

2. History
The metric system evolved over the years and in the 1960’s was named the International System of Measurement (SI for short).
Scientific standards were set with the gram, meter, kelvin, second, ampere, candela, & in 1971 – the mole
Ampere – electrical current candela measures light
Mole – used in chemistry to measure the volume of elements

3. Advantages of Metric System
No numbers to memorize
Only 30 individual units
Easy to say and write
No fractions only decimals
World standard
Converts easily by multiples of 10.

4. Units of Measurement Examples: Kilometer Hectometer Decameter Meter
Prefixes and Multiplier:
Kilo = 1000
Hecto = 100
Deca = 10
Meter/Gram/Liter = 1
Deci = .1
Centi = .01
Milli = .001
Examples:
Kilometer
Hectometer
Decameter
Meter
Decimeter
Centimeter
Millimeter

5. Length:
The standard unit of length in the metric system is the meter. Other units of length and their equivalents in meters are as follows: 1 millimeter = meter 1 centimeter = 0.01 meter 1 decimeter = 0.1 meter 1 decameter = 10 meters
1 hectometer = 100 meters
1 kilometer = 1000 meters

6. Metric Length If you need to measure length, you use the “meter”
If you need to measure longer lengths, you can use the kilometer
Lets say you live 10 miles from school
10 miles = meters
16093 is a large number, so you can move the decimal 3 spots to make it 16.1 kilometers

7. Abbreviations:
We abbreviate these lengths as follows: 1 millimeter = 1 mm 1 centimeter = 1 cm 1 meter = 1 m 1 decimeter = 1 dm 1 kilometer = 1 km

8. Examples:
For reference, 1 meter is a little longer than 1 yard or 3 feet. It is about half the height of a very tall adult. A centimeter is nearly the diameter of a dime, a little less than half an inch. A millimeter is about the thickness of a dime.

9. Who Does Not Use It?
The only countries not to use the Metric System are the U.S., Myanmar, and Liberia

10. English to Metric Conversions
39,370 inches = 1 kilometer
feet = 1 kilometer
.62 miles = 1 kilometer
39 inches = 1 meter
3.28 feet = 1 meter
1 inch = 254 mm
1 inch = 2.54 cm
1 foot = cm
1 yard = cm
1 yard = .914 m
1 mile = m
1 mile = km
You do not need to know these. They are just for you to get an idea of how these systems compare.

11. Comparisons

12. Metric Measurements
The 3 main measurements are the gram (weight), meter (length), & liter (volume)

14. Metric Prefixes These prefixes are based on powers of 10.
What does this mean?
From each prefix every “step” is either:
10 times larger or
10 times smaller
For example
Centimeters are 10 times larger than millimeters
1 centimeter = 10 millimeters

15. Metric Prefixes For each “step” to right, you are multiplying by 10
For example, let’s go from a base unit to centi
1 liter = 10 deciliters = 100 centiliters
2 grams = 20 decigrams = 200 centigrams

16. Summary Summary Base units in the metric system are meter, liter, gram
Metric system is based on powers of 10
For conversions within the metric system, each “step” is 1 decimal place to the right or left