1. Units of
Measurement
Ken Rogers
Miami Killian

2. What we’re going to be doing is similar to what is done with money (currency).
$ 1.00
Think of the dollar as the main unit for measuring money.
Based on that, you have smaller units
that are given names.
$0.25
$0.05
$0.01
penny
nickel
quarter

3. = ? ? = What we’re going to learn are units for measuring. .
and the smaller (and larger) units and their names. .
and then, later, the relationships between these units.
Relationships similar to: = ? ? =

4. That’s French meaning International System of Units.
The international unit system is called Le Systeme International d’Unites, abbreviated SI.
That’s French meaning International System of Units.
We’ll discuss the basic units of this system along with the SI prefixes.

5. Mass The basic unit for measuring mass is the kilogram.
Your textbook is about 2 kilograms.
The instrument we’ll use for measuring mass is a laboratory balance.

6. Mass and weight are not quite the same.
When any mass is near a massive object like the earth, gravity gives the mass its weight.
An example would be objects in outer space would be weightless but they would still have mass.

7. Length or distance The SI unit for measuring length is the meter.
A meter is a little bigger than 3 feet (a yard).
Length is usually measured with a ruler.

8. Volume Volume is the amount of space (or room) occupied by an object.
The SI unit for measuring volume is the derived unit a cubic meter, m3.
However, a cube this big (1 meter high, 1 meter wide, and 1 meter in length) is too big to measure most objects.
So a cube was made that has dimensions 1/10 of a meter ( 1 decimeter).
This cube is a liter.

9. A cubic meter, m3, is about the size of a desk.

10. 1m
1m3 = 1m
1 meter

11. 1 liter
1 m3

12. This is a liter.
So, how big is a liter?

13. The equipment we’ll be using to measure volume will be . . .
beaker
graduated cylinder
Erlenmeyer flask

14. 200 mL Beaker The glassware is made to measure volume in milliliters.
180
160
140
120
100 80 60 40 20
The glassware is made to measure volume in milliliters.
200 mL
Beaker

15. Abbreviations meter m SI unit for mass is ? kg gram g liter L
Capital L is used because lower case L looks like a 1
12L instead of 12l

16. Measurement Systems
American
Metric SI
length
foot
meter
meter
mass
pound
gram
kilogram
volume
gallon
liter m3

17. Now, along with the units of meters, grams and liters, we’ll be using prefixes.
Let’s start with the biggest prefixes and work to the prefixes with the smallest meaning.

18. SI Prefixes
unit exponential
Prefix abbreviation factor meaning
Tera T ,000,000,000,000
trillion
Giga G ,000,000,000
billion
Mega M ,000,000
million
Kilo k ,000
Hecto h
Deka da
SI unit o
Deci d /10
Centi c /100
Milli m /1000
Micro m /1,000,000
Greek letter, mu
Nano n /1,000,000,000

19. The SI prefixes are used in conjunction with the SI units to create new units with either greater or smaller magnitude.
For example when the prefix, kilo, is used with meter to make kilometer, the new unit is 1000 times larger.
In other words, a kilometer is equal to 1000 meters.
1 km = 1000 m
The abbreviation for kilo is k and the abbreviation for meter is m. So a kilometer is abbreviated km.

20. The prefix, milli, means 1/1000.
Combine that with meter to make millimeter.
A millimeter is equal to 1/1,000 of a meter.
(about the thickness of your fingernail)
1 mm = 1/1000 m
The abbreviation for milli is m and the abbreviation for meter is also m. So a millimeter is abbreviated mm.

21. The amounts are usually measured in milligrams or micrograms.
The vitamins and minerals in food that is needed by your body every day are very small amounts.
The amounts are usually measured in milligrams or micrograms.
One gram is about the mass (weight) of a dollar bill.
A microgram is 1/1,000,000 (one millionth) of a gram.
1 mg = 1/1,000,000 gram
Or another way of thinking about is, it takes 1,000,000 mg to equal one gram.
1,000,000 mg = 1gram

22. Remember the cubic meter . . .
. . . being too big for practical purposes?

23. So a cube was made that was
1 liter
So a cube was made that was
1 liter = 1 dm3
1/10
as big as a meter.
That would make it a
cubic decimeter.

24. Review m3 The main SI units are: cubic meter (m3) Length: meter (m)
Mass: kilogram (kg)
Volume:
Prefixes:
kilo k
deci
d 1/10
centi
c 1/100
micro m n
giga
nano
G 109 m3
= dm3
= liter
1000

25. Quiz

26. SI Units Name________________
Period ______ Date _____

27. 1. The main SI unit for measuring length or distance is a ____.
2. The main SI unit for measuring mass is a ________.
3. The main SI unit for measuring volume is a _________.
(but it’s usually too big).
4. Instead of using that unit, a smaller unit that is a cubic
decimeter is used. This dm3 is called a ______________.
5. A dollar bill has a mass of about ___________.
6. There are 3 pieces of lab equipment for measuring volume.
Name one._____________________

28. 7. All 3 pieces measure volume in what units? _____________
8. What is the prefix meaning 1000? __________
9. What is its abbreviation? _____
10. The prefix centi- means _____________.
11. The prefix meaning 1/1000 is _______________.
12. Giga means __________________.
13. What’s the difference between mass and weight?

29. 13 points
0 – 1 A
2 B
3 – 4 C
5 D
6 or more F