Transcript Chapter 1 The World of Physical Science

QUICK QUIZ TODAY
 1. List the 6 steps that make up the
scientific method
 2. What is a hypothesis?
 3. Why is it important to communicate the
findings from our experiments?
Chapter 1
The World of
Physical Science
Physical Science
The study of matter and energy.
Matter is the “stuff” that everything is made
of. Even the smallest of things you cant
see.
All matter has energy even things that are
not moving.
Scientific Theories
A theory is a way to explain why something
has happened. It is based on many tests
and observations.
They may be wrong.
How is a theory different from a hypothesis?
Scientific Laws
 In science a law is a summary of many
experimental results and observations.
 A law tells you how something works. It is
a statement that describes patterns in
nature with no known exceptions.
 Laws only tell you what happens not why
something happens.
Communicate Results
 It is very important to share your results
with others.
 You may give a presentation, write a
paper, or create a website.
 This allows others to test or change your
experiment.
Technology
 Is the application of knowledge, tools and
materials to solve problems and
accomplish tasks.
 What are some examples of technology
that we use today?
Quiz # 2
1. Physical Science is the study of
a.
Matter & Motion
b.
Matter & Energy
c.
Energy & Motion
d.
Matter & Composition
2. For a hypothesis to be valid, it must be
a.
Testable
b.
Supported by evidence
c.
Made into a law
d.
Both a & b
Quiz continued…
3. The statement “Sheila has a stain on her shirt” is an
example of a(n)
a. Law
b. Hypothesis
c. Observation
d. Prediction
4. A hypothesis is often developed out of
a. Observations
b. Experiments
c. Laws
d. Both (a) & (b)
Quiz continued…
5. Explain why the results of one
experiment are never really final results.
http://www.youtube.com/watch?v=DQPQ_q59xyw
International System of
Units
 Today most scientists in almost all
countries use the international system of
units or SI.
 The system is based on the number 10
which makes conversions from one unit
to another easy to do.
 Why do we use SI?
Length
The distance from one point to another
point.
 Base unit is the meter (m).
 Tool is the metric ruler
Meter
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kilometer (km) = 1,000 m
decimeter (dm) = 0.1 m
centimeter (cm) = 0.01m
millimeter (mm) = 0.001m
micrometer ( ) = 0.000 001m
nanometer (nm) = 0.000 000 001m
Measure this…
1. How many centimeters is your desk? _____
2. How many meters is the back counter?____
3. How many millimeters is your pencil? _____
4. How many kilometers is 1 meter? ______
Volume
The amount of space a substance
occupies.
 Base unit is the liter (L).
 Tools: metric ruler for regular solids or
graduated cylinder for liquids.
Cubic Meter
 Cubic meter (m³)
 Cubic centimeter (cm³) 1 cm³ = 0.000 001 m³
 Liter (L) 1L =dm³ = 0.001m³
 Mililiter (mL) 1 mL= 0.001 L =1 cm³
Mass
The amount of matter in a substance.

Base unit - kilogram (kg).
Gram (g) 1 g = 0.001 kg
Milligram (mg) 1 mg = 0.000 001kg
Temperature
The amount of kinetic energy a substance has.
 SI unit is the Kelvin (K).
Celsius (°C)
0°C = 273 K
100 °C = 373 K
 Tool is the thermometer
Area
The number of square
units inside a figure
A = LW
Area = Length x Width
Density
 Density is a comparison of how much
matter there is in a certain amount of
space.
Which one is more dense?
 Demonstration: People in a square
 How about this: Which square is more
dense?
Which one is more dense?
 Now which one is more dense?
What is density?
 Density = mass OR
volume
 Units for density: g
cm3
mass ÷ volume.
ALWAYS
REMEMBER
.
UNITS!
Let’s try a density problem
together
 Frank has a paper clip. It has a mass of
9g and a volume of 3cm3. What is its
density?
 Frank also has an eraser. It has a mass
of 3g, and a volume of 1cm3. What is its
density?