1. Types of quantitative observations

2. International System of Units
1. Known as SI units (System International)
Official name of the metric system.
Is an “universal system of measurement” in the scientific world.
What does “Universal” mean?
Used by all scientist worldwide regardless of their language.

3. Why does science need an universal system of measurement
Why does science need an universal system of measurement? (think of the scientific method)
Step 6 of the scientific method
Results of an experiment must be able to be replicated by other scientist
Metric system is also easier to used.
Why?
Based on multiples and divisions of 10

4. 2. The metric/SI system is also easier to use.
Why?
You only need to move a decimal point to the left or to the right.

5. Length: distance between 2 points
SI base unit =
meter
Instrument used to measure length?
metric ruler or meter stick
Divisions of a meter =
dm, cm, mm
Multiples of a meter =
Km, Hm, Dm

6. Let’s practice!!!!!!!

7. Answers: 1. Measure the length of this rectangle in centimeters:
2. Measure the height of this rectangle in centimeters:
3. Measure the length of this line in millimeters:
Height
Length

8. Conversions
-Changing from one unit to another.
-Uses prefixes to describe divisions and multiples
of a base unit.
Kilo Hecto Deca BASE deci centi milli UNIT
King Henry died----gulp----drinking chocolate milk

9. Metric –vs- English Conversions
Kilo Hecto Deca BASE deci centi milli
UNIT
Easier:
10 Kilometers = how many meters?
500 centimeters = how many meters?
Harder:
10 miles = how many inches?
10 Km move decimal 3 places to right = meters
500 cm move decimal 2 places to left = 5. meters
10 miles x 5280 feet x 12 inches = inches
1 mile foot

10. AREA What is the area of an object? = 50 cm2 L x W = meters squared

11. Solid volume:
How much space an object occupies
LxWxH = m3

12. Temperature SI base unit = degrees Celsius Instrument used to measure:
Thermometer
Therm =
heat

13. Let’s do a comparison: ° C x 9/5 + 32 = °F (°F - 32) x 5/9 = °C
CELSIUS VS FAHRENHEIT
WATER BOILS
BODY TEMP
ROOM TEMP
WATER FREEZES
212
100 37
98.6 22 32
° C  x  9/ = °F
(°F  -  32)  x  5/9 = °C

14. BOILING
BODY TEMP
37 C
98.6 C
ROOM TEMP 22
FREEZING

15. Volume How much space an object occupies.
Two types of volume: Liquid and solid
Liquid volume:
SI base unit =
liter (Kl, Hl, Dl, l, dl, cl, ml)

16. Instrument used to measure liquid volume?
Graduated Cylinder
Beaker
Flask
Graduated Cylinder

17. Read the bottom of the meniscus.
= 43 ml

18. Solid Volume: Amount of space an object occupies.
Length x Width x Height
SI label:
m3 or cm3

19. Not all solids have a regular shape!!
Sometimes the length , width and height can not be determined
Regularly shaped Irregularly shaped

20. Solid volume of a irregular shaped object
Use water displacement
to determine volume

21. Water Displacement Record volume of water in graduated cylinder. 7ml
Add object
Record volume of water after object is added. 9ml
The difference is the volume of the object 2ml
Change unit to cm3
Answer: 2 cm3

22. Mass The amount of matter in an object. SI unit:
-grams (Kg, Hg, Dg, g, dg, cg, mg)
Instrument or tool to used to determine mass?
-Balance

23. Mass is different than weight
Mass is a constant value, it is not influenced by the pull of gravity. Weight is based upon the pull of gravity. The pull of gravity varies based on an objects distance from the center of the Earth.

24. Top of mountain Sea level Mass stayed constant
Mass: 68 Kg
Weight: 147 pounds
Mass stayed constant
Weight decreased due to a lesser pull of gravity.
Top of mountain
Mass: 68 Kg
Weight: 150 pounds
Sea level

25. Density: The mass of an object per unit volume. mass / volume =
g/L (liquid density)
g/m3 (solid density)

26. Density Determination
1 Kg of Stones
1 Kg of Feathers
Mass of stones = 1 Kg
Volume of stones = 10 m3
Density = mass = Kg = 2
volume m3
Mass of feathers = 1 Kg
Volume of feathers = 100 m3
Density = mass = Kg = .001
volume m3

27. Less dense than the liquid More dense than the liquid
More or less dense?????
Less dense than the liquid
More dense than the liquid