Post on 27-Dec-2015
Introduction to
Science
Why Science?
It all starts with a …
What is science?
A method (system) of organizing curiosities.
Why does iron rust?
Why do dogs bark?
How do penguins stay warm in the
cold?Why can’t we float on air?
True or False: Everything in science is a fact.
FALSE! Believe it or not, not everything that we will explore this year is proven to be 100% true.
Science is always changing! We’re even debating whether to
add in two more planets into our solar system or keep it to our familiar nine.
Fact vs. Inference vs. Opinion
Fact: something that can be proven true and is always found to be true. “I am 5 feet 7 inches tall.”
Inference: an idea based on facts that tries to explain facts. “It is going to be hot today because it is already
75 degrees outside!” Opinion: an expression of feelings or
attitude towards something. Miss Zitzmann is the coolest science teacher
ever!
What is Life Science?
Life Science: Study of living things.
How to think like a scientist…
No matter what a scientist may be curious about or what they are studying, they all use similar methods to investigate.
They all follow the scientific method. This helps scientists answer a question or solve a problem.
The Scientific Method
It can be used to study anything from a leaf to a dog to the entire Universe!!!!
Step One: State the Problem…
Did you ever wonder why something happens or where something comes from?
Just about everything starts with a question.
Usually, scientists come up with questions by looking at the world around them. "Hey look! What's that?"
Step Two: Make Observations
Observation: information (data) gathered by using your senses.
Senses: sight, smell, touch, hear, taste DO NOT EVER TASTE ANYTHING UNLESS
INSTRUCTED IN SCIENCE CLASS!!!! Measurement: an observation
expressed as a number with a unit. All measurements expressed in SI
units…(more later on these).
Step Three: Form a Hypothesis
Hypothesis- an educated guess. It is a possible explanation or
possible answer to the question you develop.
Usually in the form of: “If blah blah blah, then blah blah
blah.”
Step Four: Do the
Experiment
Test out your hypothesis and collect data.
Things to consider: Control group: used for comparison to see
if any change actually occurs during an experiment. The factors in this group are NOT manipulated or changed.
Experimental group(s): these groups experience manipulations/changes with their factors (called variable)
Why do we use experimental and control
groups? Because the variable differs between
the control group and experimental groups, scientists can be more certain that differences in the variable are causing any differences observed in the outcome of the experiment.
Was the one factor (variable) that you changed actually causing differences in the outcome of your experiment?
Step Five: Analyze the Results
Organize and analyze your data in order to come to a conclusion on whether or not your hypothesis was correct.
Step Six: Draw a conclusion
Were you correct? It is okay to be wrong!!! Some
scientists may go through their whole life and never come up with a hypothesis that actually worked out! Just think about how many attempts
have been made to cure cancer…unfortunately there are lots of failed hypotheses.
Measurement
History of Measurement
There are many different systems of measurement used throughout the world.
At one point, an inch was considered the size of one’s thumb; a yard from one’s neck to tip of one’s index finger; and a foot the length of one’s foot.
So why do we not use this system anymore? Consider the difference between the
following…
Sasquatch vs. Mini-Me
So how do we make it fair?
We use SI Units! SI Units: (International System of
Units). Used by most scientists in all countries.
The United States is actually the only country that uses feet, yards, and inches. The rest of the world uses SI Units.
Common SI Units
Length Meter (m)
Volume Cubic meter (cm3)
Mass Kilogram (kg)
Temperature Kelvin (K)
Length
Length: distance between two points.
Measured using a ruler, tape measure.
Different SI Units for Measurement
• We will work with the following measurements for length.• km=kilometer• hm=hectometer• dam=dekameter• m=meter• dm=decimeter• cm=centimeter• mm=millimeter
How do we convert between units?
SI units are based on multiples of 10…
km hm dam m dm cmmm
__ 10__ 10__10 __ 10 __ 10 __ 10
Or in another form..
1km= 1m X 10 X 10 X 10
1hm= 1m X 10 X 10
1dam=1m X 10
1m = 1m
1dm= 1m / 10
1cm= 1m /10 / 10
1mm= 1m / 10 /10 /10
Area
Area: measure of how much surface an object has.
To find area use the following formula: Area= Length X Width. Area = L X W Answers reported in square units or
units2 (ex:cm2)
Example Area Problem…
Find the area of the following piece of wood.
A = L X W =5cm X 3cm =15 cm2
5cm
3cm
Volume
Volume: The amount of space something takes up.
Measured using either a ruler or a graduated cylinder.
Volume = Length X Width X Height
V= L X W X H Answers are reported in
milliliters, liters, or units3 (ex: mL, L, or cm3).
Example Volume Problem
Find the volume of the fish tank.
V = L X W X H =
20 cm
24 cm
10 cm
How to read a graduated cylinder
Find the meniscus.
Read from the bottom of the meniscus at eye level!.
How to find the volume of oddly shaped
objects…Measure how much fluid the object displaces.
Step 1: Fill a graduated cylinder to an easy volume to work with (let’s say 100 mL).
Step 2: Place object in graduated cylinder. Step 3: Measure how much the water goes
up. (Let’s say the water went up to 150 mL). Step 4: Subtract your final volume from
your starting volume to get the volume of the object (150 mL – 100mL = 50mL!!)
Add rock
Start: 100mL End: 150mL
Volume of Rock=
50mL
Mass
Mass: amount of matter that makes up an object.
Measured using a triple beam balance. Answers are reported in grams.
Temperature
Temperature: Measure of how fast the molecules in a substance are moving (the faster the molecules are moving, the hotter the substance).
Answers reported using Kelvins (K) and Celcius (oC).
Measured using a thermometer.
Density
Density: measure of how packed together the molecules of a substance are.
To find the density of a substance use the formula: Density = mass/volume D = m / v
Example Density Problem
Types of Graphs
Circle, Line, and Bar Graphs
Circle/Pie Graphs
Compares proportions or percents.
Should only be used when all parts add up to one complete item.
Guidelines Include legend of slices Include data labels (%) on
slices
Percent of Foods in Daily Diet
30%55%
15%
FatsCarbohydratesProteins
Bar Graphs
Compares “Discrete” objects or items
Can be used over time if time intervals vary
Guidelines Add data labels Label all axes Title chart Avoid 3-D
Form I Student Height
010203040506070
Chuck Bob Sue
Student Name
Hei
gh
t (I
nch
es)
Line Graphs
Shows trends or changes over time.
Should only be used with continuous “X” variables.
Guidelines: Label all axes and title
graph Be sure time intervals
are appropriate distances apart on “X” axis!
Water Temperature Over Time
0
10
20
30
1 2 3 4 5 6 7 8 9
Time (Minutes)D
egre
es (
Cel
siu
s)