Measuring SI ze

What is SI?

(or International System of Units) Systeme Internationale d’Unites (or International System of Units) Abbreviated SI (System of International Measures) It is the internationally accepted standard units of measure. Formerly known as…

The Metric System

The SI Base Units are… What it measures Base Unit Length Meter (m) Mass Kilogram (kg) Volume Liter (l or L or ℓ) Time Seconds (s) Temperature Kelvin (K) Amount of a substance Mole (mol) Electric Current Ampere (A) Luminous Intensity Candela (cd)

Basic units of the SI system: Length = meters (m) Mass = gram (g) Volume = liter (L or l)

“I’m ten times better than the way you measure now!” The SI System “I’m ten times better than the way you measure now!”

Let’s see why… Fill in the blanks (do the math mentally): 13 miles = ____yards ____feet ____inches 2 1/2 gallons = ____quarts ____pints ____cups ____ounces (22,880 yds) (68,640 ft.) (823,680 in) (10) (20 p) (40 cups) (320 ounces)

That was not the SI system! What number is the SI system based on? SI 10

Let’s see why 10 is an easy base to use.

Multiply each of the following numbers by 10 15 x 10 = 235 x 10 = 12.4 x 10 = 43.2 x 10 = 853.56 x 10 =

Multiply each of the following numbers by 10 15 x 10 = 150 235 x 10 = 12.4 x 10 = 43.2 x 10 = 853.56 x 10 =

Multiply each of the following numbers by 10 15 x 10 = 150 235 x 10 = 2350 12.4 x 10 = 43.2 x 10 = 853.56 x 10 =

Multiply each of the following numbers by 10 15 x 10 = 150 235 x 10 = 2350 12.4 x 10 = 124 43.2 x 10 = 853.56 x 10 =

Multiply each of the following numbers by 10 15 x 10 = 150 235 x 10 = 2350 12.4 x 10 = 124 43.2 x 10 = 432 853.56 x 10 =

Multiply each of the following numbers by 10 15 x 10 = 150 235 x 10 = 2350 12.4 x 10 = 124 43.2 x 10 = 432 853.56 x 10 = 8535.6

Multiply each of the following numbers by 100 15 x 100 = 235 x 100 = 12.4 x 100 = 43.2 x 100 = 853.56 x 100 =

Multiply each of the following numbers by 100 15 x 100 = 1500 235 x 100 = 12.4 x 100 = 43.2 x 100 = 853.56 x 100 =

Multiply each of the following numbers by 100 15 x 100 = 1500 235 x 100 = 23500 12.4 x 100 = 43.2 x 100 = 853.56 x 100 =

Multiply each of the following numbers by 100 15 x 100 = 1500 235 x 100 = 23500 12.4 x 100 = 1240 43.2 x 100 = 853.56 x 100 =

Multiply each of the following numbers by 100 15 x 100 = 1500 235 x 100 = 23500 12.4 x 100 = 1240 43.2 x 100 = 4320 853.56 x 100 =

Multiply each of the following numbers by 100 15 x 100 = 1500 235 x 100 = 23500 12.4 x 100 = 1240 43.2 x 100 = 4320 853.56 x 100 = 85356

Divide each of the following numbers by 10 230  10 = 4500  10 = 123.5  10 = 21.6  10 = 8.465  10 =

Divide each of the following numbers by 10 230  10 = 23 4500  10 = 123.5  10 = 21.6  10 = 8.465  10 =

Divide each of the following numbers by 10 230  10 = 23 4500  10 = 450 123.5  10 = 21.6  10 = 8.465  10 =

Divide each of the following numbers by 10 230  10 = 23 4500  10 = 450 123.5  10 = 12.35 21.6  10 = 8.465  10 =

Divide each of the following numbers by 10 230  10 = 23 4500  10 = 450 123.5  10 = 12.35 21.6  10 = 2.16 8.465  10 =

Divide each of the following numbers by 10 230  10 = 23 4500  10 = 450 123.5  10 = 12.35 21.6  10 = 2.16 8.465  10 = .8465

Divide each of the following numbers by 100 230  100 = 4500  100 = 123.5  100 = 21.6  100 = 8.465  100 =

Divide each of the following numbers by 100 230  100 = 2.30 4500  100 = 123.5  100 = 21.6  100 = 8.465  100 =

Divide each of the following numbers by 100 230  100 = 2.30 4500  100 = 45.00 123.5  100 = 21.6  100 = 8.465  100 =

Divide each of the following numbers by 100 230  100 = 2.30 4500  100 = 45.00 123.5  100 = 1.235 21.6  100 = 8.465  100 =

Divide each of the following numbers by 100 230  100 = 2.30 4500  100 = 45.00 123.5  100 = 1.235 21.6  100 = .216 8.465  100 =

Divide each of the following numbers by 100 230  100 = 2.30 4500  100 = 45.00 123.5  100 = 1.235 21.6  100 = .216 8.465  100 = .08465

Nice Job! If you can multiply & divide by 10 (or any power of 10), then the metric system will be easy for you.

 Checkpoint: Metric units are based on multiples of what number? Multiply--Move the decimal to the right Divide--Move the decimal to the left

Scientists created different sized units of measure by adding prefixes to the base units. It’s kind of like using a cup as a basic measure and using 1/2 a cup, 1/4 of a cup, or 1/3 of a cup for the smaller measures.

Numerical value in Base units Prefix Symbol Numerical value in Base units Power of 10 value Giga G 1,000,000,000 109 Mega M 1,000,000 106 Kilo- k 1000 103 Hecto- h 100 102 Deka- da 10 101 Base Unit -- 1 Deci- D 0.1 10-1 Centi- c 0.01 10-2 Milli- m 0.001 10-3 Nano n 0.000000001 10-9 Pico P 0.000000000001 10-12 The SI Prefixes

What is length? Length is the distance from one point to another

The basic unit of length in the SI system is the … meter

Pause… How big do you think a meter is? Find something you think is a meter in length.

THE METER The meter is the starting point for measuring length in the metric system. START

Here’s a meter stick!

It takes 10 decimeters to make up 1 meter.

It takes 10 centimeters to make up 1 decimeter.

1 decimeter = 10 centimeters, If 1 meter = 10 decimeters and 1 decimeter = 10 centimeters, then how many centimeters make up 1 meter?

That’s right! 1 meter = 100 centimeters

100centimeters = 1 meter

It takes 10 millimeters to make up 1 centimeter. Boy, that’s small!

If 1 meter = 10 decimeters and 1 decimeter = 10 centimeters and 1centimeter = 10 millimeters then how many millimeters make up 1 meter?

That’s right! 1000 millimeters = 1 meter

It takes 10 millimeters to make up 1 centimeter. Millimeters are so small that they almost run together.

Checkpoint One centimeter is divided into how many millimeters? 10 millimeters (mm)

Now let’s take a closer look at some measuring devices.

This is a magnified image of a ruler/meter stick. 1 2 3 4 This is one centimeter.

This is a magnified image of a ruler/meter stick. 1 2 3 4 This is half of a centimeter.

This is a magnified image of a ruler/meter stick. 1 2 3 4 This is one millimeter.

This key measures 3 cm. 1 2 3 4

Or you could say that it measures 30 mm. 1 2 3 4

This key measures 2.5 cm. 1 2 3 4

Or, you could say that it measures 25 mm. 1 2 3 4

1 2 3 4 This toy car measures 4.2 cm.

1 2 3 4 Or, you could say it measures 42 mm.

The metric system deals with powers of 10 1 meter = 10 decimeters = 100 centimeters = 1000 millimeters

How many centimeters make up 2 meters?

That’s right! There are 200 centimeters in 2 meters.

How many millimeters make up 2 meters?

That’s right! There are 2000 millimeters in 2 meters.

How many decimeters make up 2 meters?

That’s right! There are 20 decimeters in 2 meters.

The metric system really is 10 times better than our standard system of measurement. It is very easy to convert from one unit to another.

You must simply multiply by 10, 100, or 1000 You must simply multiply by 10, 100, or 1000. OR You must simply divide by 10, 100, or 1000.

The end.