1. Bell work:
1. If one pencil is 5.2 paper clips long, then how many paper clips is 3 pencils? 2. Re-write this number in scientific notation: 93,000,000 miles

2. What do we need to measure?
What tools/instruments do we use to measure?
Linear: length, width (distance)
Area:
Volume:
Mass:
Weight
Time
Temperature
Ruler
Micrometer
Graduated cylinders
Balance / scale
Stop watch
Thermometer
Quantitative Data
What units do we measure in?
How do we read and record measurements properly?
Universal Standard Units:
Meter (length)
Liter (volume)
Gram (mass /weight)
Celsius (temperature
Use same scale (metric) NO ENGLISH UNITS!
Use decimal places
Accuracy and Precision
Significant figures
Scientific Notation
Direct and Indirect measurements

3. Why do we need to be able to measure things?
To make sense, all measurements need both . . .
Why do we need to be able to measure things?
Suppose we wanted to measure a 2 x 4 for building a house.
Units by themselves don’t make sense.
Numbers by themselves don’t make sense.
A Number
and
a Unit!
A board is meters long
A board is 350 long
Any Ideas?

4. Basic Types of Measurement
Length: measures distance between objects
Volume: measures the amount of space something takes up
Mass: measures the amount of matter in an object
In SI the basic units are:
Length is the meter
Mass is the gram
Volume is the liter (liquid)
Temperature is Celsius

5. Measurement System Comparisons
ENGLISH
SI SYSTEM
LENGTH
Yard / Inch
Meter / Centimeter
MASS
Ounce / Pound
Gram / Kilogram
VOLUME
Quart
Liter
TEMPERATURE
Fahrenheit
Celsius / Kelvin
TIME
Second
All Measurement systems have standards. Standards are exact quantities that everyone agrees to use as a basis of comparison.

6. Why use the SI System?
In the U.S. we use the English or Standard System, most of the rest of the world uses the Metric or SI System.
Scientists use the SI System worldwide because:
Measurements are easily understood by all scientists
Measurements are easier to convert than the English system
The SI (International System of Units) system is the measurement system used by scientists.

7. Map of Countries using English Units
Liberia
Burma

8. Basic Types of Measurement
Length: measures distance between objects
Volume: measures the amount of space something takes up
Mass: measures the amount of matter in an object
Other Types of measurement include:
time
temperature
density pH

9. The SI System uses the following prefixes:
Kilo
1000
Hecto
100
Deca 10
UNIT 1
Deci
1/10
Centi
1/100
Milli
1/1000
This system works with any
SI measurement.
The UNIT becomes whichever type of measurement you are making. (mass, volume, or length)
It is the same system regardless if you are measuring length, mass, or volume.

10. centi gram It works for all types of measurement.
If you’re measuring . . .
Length then it is the meter (kilometer, decameter, etc.)
Mass then it is the gram (centigram, milligram, etc.)
Volume then it is the liter (deciliter, hectoliter, etc.)
centi
gram
The first part of the term indicates the amount, the second part indicates the type of measurement.

11. How does converting units work?
Unlike the English system converting in the SI System is very easy. For Example in the English system if you wanted to know how many inches in 2 miles what would you do?
Take the number of miles (2).
Multiply it by the number of feet in a mile (5,280).
Multiply that by the number of inches in a foot (12).
ANSWER: 126,720 inches in 2 miles

12. The SI system is much easier.
For example in the metric system if you wanted to know how many centimeters were in 3 meters, what would you do?
Find the unit you have (meters).
Find the unit you are changing to (centimeters).
Count the number of units in-between (2).
Move the decimal point that many spaces, in the same direction you counted (right).
3 meters =
300 centimeters
Kilo Hecto Deca UNIT Deci Centi Milli

13. Kilo Hecto Deca UNIT Deci Centi Milli
More Conversions . . .
2,321.0 millimeters to meters
= meters
521.0 grams to hectograms
= hectograms
NOTE: The digits aren’t changing, the position of the decimal is. In the English system the whole number changes!
Kilo Hecto Deca UNIT Deci Centi Milli

14. Things to Remember All measurements need a number and a unit!
Basic units of Measurement (meter, liter, gram)
How to convert metric units

15. Precision and Accuracy
Precision is a description of how close measurements are to each other.
Accuracy is comparing your measurement to the actual or accepted value.

16. Measurement Review Measurements need a number and a unit!
Basic units of Measurement (meter, liter, gram)
How to convert metric units
Be able to make basic measurements of volume, length, and mass
Vocabulary words

17. State the same measurement in two different units
length
10.0 in.
25.4 cm

18. Conversion Factors
Fractions in which the numerator and denominator are EQUAL quantities expressed in different units
Example: in. = 2.54 cm
Factors: 1 in and cm
2.54 cm in.

19. Conversion factor 2.5 hr x 60 min = 150 min 1 hr cancel
How many minutes are in 2.5 hours?
Conversion factor
2.5 hr x min = min
1 hr
cancel
By using dimensional analysis / factor-label method, the UNITS ensure that you have the conversion right side up, and the UNITS are calculated as well as the numbers!

20. = 29 quarters Sample Problem
You have $7.25 in your pocket in quarters. How many quarters do you have?
7.25 dollars quarters
1 dollar
= 29 quarters X

21. Kilo Hecto Deca UNIT Deci Centi Milli
A rattlesnake is 2.44 m long. How long is the snake in cm?
a) cm
b) 244 cm
c) 24.4 cm
Kilo Hecto Deca UNIT Deci Centi Milli

22. Solution
A rattlesnake is 2.44 m long. How long is the snake in cm?
b) 244 cm
2.44 m x cm = 244 cm
1 m

23. Amount of People in the World.
There are 6,900,000,000 people in the world.
What is a better way to write this HUGE value?
Scientific Notation
6.9 X 109 People
Why are we able to write the number like this?

24. 11 11 cm 11. cm 11.0 cm cm

25. Significant Figures – long story short, this is how well you measured something.
The most confusing parts are the zeros
Rules
If there is a decimal point AND non-zeros before and after it, then all numbers are significant
Ex: 45.65cm
If the number is not greater than 1 all zeros up to the first non-zero are not significant, but everything else after that is significant.
Ex: cm
If there is no decimal, any non-zero numbers are significant, as well as any zeros that are in between non-zeros.
Ex: 30560cm

26. Sig-Fig “Box Method”
Step 1
Draw a box around ALL nonzero digits, beginning with the leftmost nonzero digit and ending with the rightmost nonzero digit in the number.  
Step 2
If a decimal is present, draw a box around any trailing zeros.  
Step 3
Consider any and all boxed digits significant.
9 sig. figs.

27. How many significant figures are in the following:
203.4
7600
7600.
760.00 4 2 2 5

28. Bell work: 4.3 18.3 1. It takes 4.3 pencils to make a book.
How many pencils does it take to make 18.3 books?
_____pencils__ x ______books___ =
1 book
3.2 beans x pencils =
1 pencil rug

29. Bellwork: 100 cm Convert 626 cm to meters:
__1m____ x ________ = _______ m
2. How many significant figures in:
5280 _____
52.80 _____
100 cm