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Notes – Unit OneMeasurements and
Properties of Materials
Measurements
Give an example of something you do that requires measuring.
What are some important things to keep in mind when making a measurement? Accuracy Units
What are units? The divisions you are measuring in, like
centimeters or inches or grams or ounces.
Reading Scales There is no such thing as a perfect
measurement! Read scales as ___________ and ___________
as possible; Use _________ scales; ___________ between divisions.
A.
B.
C.
D.
A. B.
C. D.
1.10 cm
2.45 cm
3.00 cm
4.76 cm
accurately
precisely
Estimatemetric
Volume
Definition: ____________________________________________________________ Units: ______ or ______
The amount of space an
object or material takes up
Read the
________
of the meniscus
bottom
cm3mL
Calculating VolumeMethod 1: Length x Width x
Height Measure the length, width and height
of an object and __________ them together
Example: volume of a kleenex box Length = 22.5 cm; Width = 12.0 cm; Height = 7.6 cm
Volume = ____________________ = _______
multiply
22.5 cm x 12.0 cm x 7.6 cm
2052 cm3
Method 2: Water Displacement
Add enough water to a beaker or graduated cylinder to _____________________ and record the level of the water __________________
Add the object to the water and record the new water level __________________;
Subtract the ________ volume from the _________ volume _________.
completely submerge the object
(initial volume A)
(final volume B) initial
final(B - A)
Initial Volum
e A
Final Volum
e B
Water Displacement (con’t)
Example: measure the volume of the dinosaur
Initial volume of water = ___________ Final volume of water = ___________ Volume of dinosaur = ______________ =
______
4.8 mL5.6 mL
5.6 mL – 4.8 mL 0.8
mL
Review
In your own words, what does volume measure?
What method would you use to measure the volume of a rock?
Mass Definition:__________________________ Units:__________; Always read to 0.1 gram (1 decimal place)
amount of matter in an objectgrams
(g)
Scale reads ____________373.3 gTriple Beam Balance
Practice ProblemsMeasuring Quiz
A rectangular solid measures 3.0 cm by 2.0 cm by 1.0 cm. What is the volume of the object?
Answer:
3.0 cm x 2.0 cm x 1.0 cm = 6.0 cm³
A graduated cylinder initially contains 10.0 mL of water. A gold ring is added to the water, and the water level rises to 13.6 mL. What is the volume of the ring?
Answer:
13.6 mL – 10.0 mL = 3.6 mL
If a block measuring 2.0 cm x 2.0 cm x 2.0 cm was placed in a graduated cylinder containing 20.0 mL of water, to what level would the water rise?
Answer:
2.0 cm x 2.0 cm x 2.0 cm = 8.0 cm³
20.0 mL + 8 cm³ = 28.0 mL
Read the correct volume of water in each cylinder.
A._______ B._______ C._______46 mL 2.8 mL
53 mL
What is the length of the black object?
A. __________
To what measurement is the blue arrow pointing?
B. __________
cm
41.62 cm 4.20
cm
A.What is the initial volume of water in the cylinder? __________
B.What is the final volume of water in the cylinder? __________
C.What is the volume of the fish? __________
32 mL
38 mL
6 mL
Graphing Basics
Independent vs. Dependent VariablesGraph Scales
Independent vs. Dependent Variables
Scientists use an experiment to search for ______________________________ in nature. They design an experiment so that changes to one factor cause a predictable change to another.
These changing factors are called __________. Two kinds of variables are ____________ and _____________.
cause and effect relationships
variablesdependent
independent
The independent variable is the one that is __________________________. To ensure a fair test, a good experiment has ___________ independent variable. As the scientist changes the independent variable, he observes the effect on the dependent variable.
The dependent variable ____________ the independent variable.
changed by the scientist
only ONE
depends on
For example, if you drop a tennis ball from increasing heights, the rebound height changes in response--you observe the higher the drop height, the higher the rebound height.
The scientist changes the drop height, so this is the ___________ variable.
The rebound height is the _________ variable.
independent
dependent
I = independent D = dependent
_____Height ball bounces_____Height ball is dropped from
_____Heating time_____Temperature of liquid
_____Intensity of odor_____Distance you stand from perfume
vial
D
D
D
I
I
I
I = independent D = dependent
_____Amount of water given_____Growth rate of plant
_____Flowrate of water_____Opening of faucet valve
_____Weight of pendulum_____Period of pendulum swing
D
D
D
I
I
I
Graphing Rules: Use pencil! Include a TITLE. Graph the
INDEPENDENT VARIABLE on the X-axis (horizontal );
Graph the DEPENDENT VARIALBE on the Y-axis (vertical )
LABEL each axis with both the NAME OF THE VARIABLE and the UNITS;
Drop Height vs Rebound Height
0
20
40
60
80
100
120
0 50 100 150 200
Drop Height (cm)
Reb
ou
nd
Hei
gh
t (c
m)
Graph Scales
1. Make your scales EASY to use.
2. Scale increments must be CONSISTENT.
3. Use up as MOST OF THE GRAPH SPACE.4. Increase to the top and to the right.5. Scales do not need to start at zero.6. Scales do not have to be the same on both
axes.
0 5 10 15 20 0 3 6 9 12
YES NO
0 5 10 15 20 0 5 10 20 30
YES NO
• Draw a BEST-FIT CURVE showing the TREND OF THE DATA. Do not draw dot-to-dot curves.
Heating Curve
10
20
30
40
50
60
70
80
90
0 2 4 6 8 10 12
Time (min)
Tem
p.
(C)
Heating Curve
0102030405060708090
051015202530
Time (min)
Tem
p.
(C)
YES NO
• If more than one curve is on the same graph, you must include a KEY.
Notes - Density
Density - Definition
Mass per unit volume of a substance
Think of density as the amount of matter that is packed into a given volume
Less Dense More Dense
Calculation and Units
Density = Mass__ Volume
Units = units of mass = g or g
units of volume mL cm³
Sanchez Circle
M
V D
Density and Floating
If an object floats in water, it is LESS dense than water (D < 1.0 g/mL)
If an object sinks in water, it is MORE dense than water (D > 1.0 g/mL)