Transcript chapter one - Mrs Zanolini`s Chem & Physical Science Classes

PHYSICAL SCIENCE
Mrs. J. Zanolini
CHAPTER ONE
INTRODUCTION TO SCIENCE
1.1 THE NATURE OF
SCIENCE
Is science:
a set of FACTS?
OR
an ongoing PROCESS?
BRANCHES OF SCIENCE
LIFE SCIENCE
PHYSICAL SCIENCE
EARTH SCIENCE
Let’s break down the other
branches
Life Sciences
Earth Sciences
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Biology
Botany
Zoology
Anatomy
Genetics
Medicine
Geology
Meteorology
Oceanography
Paleontology
?
?
How do pure science and
technology depend on
each other?
A ________
THEORY is an explanation for some
phenomenon that is based on observation,
experimentation, and reasoning.
The KINETIC MOLECULAR THEORY
states that molecules are in constant motion.
Use this theory to explain why the balloon
takes the shape it does.
Use the KINETIC theory to explain
why the handle of a camp fork gets hot.
LAW is a summary of a repeated
A _____
observation & many experimental
results .
A MODEL is a _______ of an object
or event.
MODELS MAY BE:
drawings
mental pictures
a set of rules
physical objects
computer pictures
Identify some models in our classroom….
Identify some models outside our classroom
THE WAY SCIENCE WORKS
1.2
The Way Science Works 1.2
• The most
important
scientific skill
is learning to
_________
________.
It is a way of THINKING
THE SCIENTIFIC METHOD is a way to
organize your thinking.
After making observations…
1. Question
2. Collect Data
3. Hypothesis
4. Experiment – only one
variable!!! All other
conditions controlled!!!
Using the Scientific Method to improve
5. Conclusion
your social life.
It is using scientific TOOLS.
Name some tools found in our classroom…
The Metric System
It is using the METRIC system of
measurement.
UNIT
TOOL
LENGTH
MASS
VOLUME
TEMPERATURE
CLICK FOR A MEASUREMENT PRESENTATION: http://videos.howstuffworks.com/hsw/5894scientific-method-length-in-metric-system-video.htm
SI - International System of Units
1. Based on multiples of 10
2. Common metric prefixes:
a.
b.
c.
d.
e.
f.
g.
h.
mega- (M)
kilo- (k)
hecto- (h)
deka- (da)
deci- (d)
centi- (c)
milli- (m)
micro- (u)
1 000 000 x
1 000 x
100 x
10 x
0.1 x
(1/10)
0.01 x (1/100)
0.001 x (1/1000)
0.000 000 001 x
Jason goes metric…
1.3 ORGANIZING DATA
LINE GRAPHS
• MOST OFTEN USED IN SCIENCE
• DISPLAY DATA THAT IS CHANGING
• TWO VARIABLES
– _______________ x axis
– _______________ y axis (depends on what happens)
How to construct a line graph
Making Science Graphs and Interpreting Data
BAR GRAPHS
• TO COMPARE DATA FOR INDIVIDUAL
ITEMS
PIE CHARTS
• TO DISPLAY DATA THAT ARE PARTS OF
A WHOLE
Accuracy or Precision?
• Accuracy vs. Precision
– Accuracy – a statement of how close a
measured value is to the true or accepted value.
– Precision – a statement of how reproducible the
measured results are.
COMPARE AND CONTRAST
ACCURACY
1.
2.
3.
4.
PRECISION
1.
2.
3.
4.
WHICH WOULD YOU PREFER?
Scientific Notation
• What- a value written as a simple number
multiplied by a power of 10.
– The sun is 9.3 X 107 miles from earth.
• Why? – Very large or very small numbers
are written this way as a form of number
“shorthand”.
Scientific Notation
What Is the Standard Form of These Tens?
2
10
3
10
4
10
5
10
100
1 000
10 000
100 000
Exponents of Ten
Notice that the number of zeros matches
the exponent number…
2
10
3
10
4
10
5
10
100
1 000
10 000
100 000
What is the Exponent Form?
•500 = 5 x 10²
•.008 = 8 x 10-³
• 789 = 7.89 x 10²
Scientific Notation and Accuracy
or is it Precision???
Why did mom use scientific notation?
Is the word “accuracy” used properly here?
Significant Figures
• Significant Figures
– The value reported for a measurement is
rounded off so that it contains only the digits
known with certainty plus one uncertain one
which is the last digit.
• Significant Figure Rules
– To determine the number of significant figures
in a reported value, start at the left and count all
digits beginning with the first non-zero digit.
Examples: 0.003040 => 4 sig. fig.
10,200 => 5 sig. fig.
Significant Figures
• Significant Figures in Calculations
– Addition & Subtraction: The number of
decimal places in the answer should be equal to
the number of decimal places in the value with
the fewest decimal places.
Example:
12.0035 g
3.72 g
0.015 g
15.74 g
(4 decimal places)
(2 decimal places)
(3 decimal places)
(2 decimal places)
Significant Figures
• Significant Figures in Calculations
– Multiplication & Division: The number of
significant figures in the answer should be the
same as the value with the fewest significant
Example:
figures.
12.36 mL
4 sig. fig.
x
2 sig. fig.
1.7 g
mL
=
21 g
2 sig. fig.
– Note: Definitions and counted numbers have an
unlimited number of significant figures.
And now to prepare for the test…
• Know the branches of science.
• Understand how pure and applied science differ.
• Know how laws, theories, and models are alike
and how they are different.
• Understand metric measurement: mass length,
and volume.
• Types of graphs and variables.
• Accuracy, precision, scientific notation.