1. or How to Know “How Much?”
The SI System or
How to Know “How Much?”

2. The Metric System Officially called the SI System
Based on increments of 10 (one decimal place or zero)
A good measurement has a number and a unit
Prefixes on the unit name tell you how many zeroes to put before or after a number
Used in every country around the world except the USA and Báhrain
The official measurement system of the USA since the late 1800s

3. Why you don’t already know the Metric System
Your parents didn’t know it
No incentive for companies to switch
You are still being taught the Imperial
System through everyday experiences
- Recipes
- Consumer goods
There is a slow, steady inclusion process

4. Base Units
Base units are defined by only one measurement

5. Length Distance from one point to another
Meters (m) are the base units (a little longer than a yard)
For smaller items, centimeters (about one knuckle), and millimeters (the thickness of a dime) are used

6. Mass Amount of substance (number of particles) in an object
Gram (g) is the base unit
It is too small for some common measurements (about 1 paper clip of matter)
Usually use the kilogram (kg) for basis of comparisons
A kilogram is a little more than 2 pounds

7. Time How long it takes for something to happen
Also called “Time Elapsed” or “Elapsed Time”
Seconds (s) are the base unit
Can lead to large numbers (1hr = 3600s)

8. Derived Units of the SI System
Derived units are defined by two or more measurements
Volume
Amount of space taken up by a substance
Liters (L) are the base units (a little more than a quart)
Liters are too large for some measurements, so milliliters (mL) are often used

9. The other derived unit Density
Amount of matter in an object divided by the space taken up by the object
“How much stuff is in how much space”
Usually expressed in grams per milliliter (g/mL) for smaller amounts
Expressed in kilograms per liter (kg/L) for larger amounts
THE NUMBER DOES NOT CHANGE

10. What would you use to measure the length of your arm?
Liters
Meters
Grams
Grams/Milliliter 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

11. What would you use to measure how much water is in a pool?
Liters
Meters
Grams
Grams/Milliliter 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

12. What would you use to measure how much sugar is in one teaspoon?
Liters
Meters
Grams
Kilograms 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

13. What would you use to measure how much you weigh?
Liters
Meters
Grams
Kilograms 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

14. What would you use to measure the width of the room?
Liters
Meters
Grams
Grams/Milliliter 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

15. Participant Scores 500 Greg Bowman Kevin Burkhart Daniel Clink
Saadia Gauthier
Jeff Greene
Ashley Hayes
Kendra Hutchinson
Brian Jones
Julian Kilner
Brandon McDonald

16. SI Prefixes Used to show a number of base units
Think of them as coefficients (multipliers)
Easy to convert by sliding the decimal

17. SI Prefixes From the largest to the smallest
kilo- hecto- deka- BASE deci- centi- milli-
/10 1/100 1/1000
“King Henry died by drinking chocolate milk.”
Put your finger on the unit you have, move it to the unit you want
Move your decimal the same number of places in the same direction that your finger moved

18. Testing your knowledge…
Answer the five questions…
Use the “Metric Ruler” to slide the decimal to get the desired units…
Ready?

19. What is 25mm in m?
2.5m
0.25m
0.025m
0.0025m 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

20. How many grams are 1.12kg? 112g 0.00112g 0.112g 1120g 20 1 2 3 4 5 6 78 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

21. How many Liters are 591mL? 0.591L 59.1L 0.059L 5.91L 20 1 2 3 4 5 6 78 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

22. What is 2.5cm in mm? 250mm .25mm 25mm 0.025mm 20 1 2 3 4 5 6 7 8 9 1011 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

23. 0.355L is how many mL? 3.55mL 35.5mL 355mL 3550mL 20 1 2 3 4 5 6 7 8 910 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

24. Participant Scores 1000 Greg Bowman Daniel Clink Jeff Greene
Kendra Hutchinson
Brian Jones
Julian Kilner
Brandon McDonald
Trevor Readdick
Chelsea Vachon
900
Kevin Burkhart