Scientific Investigation
When would we use scientific
investigation?
Observations
& Inferences
A test of your observation skills…
Observations







Use one or more of the 5 senses to gather
information
Note and record … FACTS!!!
In science, observations should never be
emotional.
Write 3 examples from this classroom:
1.
3.
2.
Inferences


Logical interpretation based upon prior
knowledge and experience
Based upon observations
List 3 inferences in the classroom
1. Just because the famous actor was seen
in a jewelry store, all the tabloids inferred
he's going to ask his singer girlfriend to
Note the Differences
• In laboratory exercises, record observations
NOT inferences
• Inferences may be used when writing the
conclusion in your lab report
Let’s test your observation skills…
Take a good look at this picture
Question 1
Are there cars parked on the sides of the
road?
Question 2
What color is the pickup truck driving in the
road?
Question 3
Any minivans around?
Question 4
What's the speed limit?
Question 5
Are there any pedestrians on the road?
Answers
1.
2.
3.
4.
5.
Yes
Blue
Yes
35 mph
No
1. There is a representation of a face on one side
of the coin.
2. The Latin word "Dei" means "God."
3. The coin was made by deeply religious people.
4. The date 1722 is printed on one side of the coin.
5. The coin was made in 1722.
More examples
What observations can
we make about this
picture?
What can we infer
based on this picture?
How many legs does the elephant
have?
Who is in this picture?
• Do you see former President Bill Clinton and Al Gore?
• Actually, it’s Clinton’s face twice with 2 different hair
cuts!
Find 3 Differences..
Find 3 Differences..
Does the square have
curved sides?
Where are those dots coming
from?!
Your
brain!
Look at the chart and say the color,
NOT the word
Your right brain tried to say the color,
but your left brain was reading the word.
Read across..
These circles are not moving, your brain is
making them appear to move. Try focusing
on one circle. It will stop moving.
Are these dots moving?
What is a Hypothesis?
Some say its an educated guess?
Think of some examples…
Can you test those?
A hypothesis isn't an educated guess.
It is a tentative explanation for an observation or scientific
problem that can be tested by further investigation
How to write a Hypothesis
How does this sound?
Bacterial growth may be affected by temperature.
How can you prove that?
If temperature is increased then bacterial growth will increase
If….then
Write this question so that it is testable:
Does spending more time on Homework
increase your chances of getting an ‘A’ in
Biology?
If I spend 1 hour each night doing homework
then I will get an “A” in biology.
If…then
If winds reach over 74 MPH then a storm is
considered a hurricane.
Pompton Lakes, NJ
Hurricane Irene? Tropical Storm Irene?
Qualitative Quantitative Data
Qualitative → Quality
Quantitative → Quantity
•
• Deals with descriptions.
• Data can be observed but not •
•
measured.
• Colors, textures, smells,
tastes, appearance, beauty,
etc.
Deals with numbers.
Data which can be measured.
Length, height, area, volume,
weight, speed, time,
temperature, humidity, sound
levels, cost, members, ages,
etc.
Qualitative/Quantitative
Arnoldii Rafflesia- Largest Flower in the world
- smells like rotting meat
-Red
-Spots
-Smells
like
rotting
meat
-Fleshy
texture
-80 cm
(about 2 1/2
feet) in
Diameter
- 9 kg (20 lbs)
-Flowering
lasts for
5-7 days
Law vs Theory
Law- A law generalizes a body of observations.
principle that appears to be without exception at the
time it is mad
Law of Gravity
Theory- A scientific theory summarizes a hypothesis or
group of hypotheses that have been supported with
repeated testing
Theory of Evolution
Theory/Law
Both a scientific theory and a scientific law
are accepted to be true by the scientific
community as a whole
In fact, some laws, such as the law of gravity, can also be
theories when taken more generally
The scientific definition of the word "theory" is different
from the colloquial sense of the word.
Presenting Data
Table vs.Graph
Why do you think information is often presented in graphs
instead of just in a list or table?
What are some kinds of graphs?
•
•
•
•
Bar graph
Line graph
Pie chart
Histogram
What is the best way to present
this data?
Dec-04 1
Dec-05 5.5
Dec-06 12
Dec-07 50
Aug-08 100
Apr-09 200
Jul-09 250
Sep-09
Dec-09
Feb-10
Jul-10
Sept-10
Jan-11
Feb-11
Jun-11
300
350
450
500
550
600
650
750
Bar Graph
Data
Energy in New Jersey
51% Nuclear
33% Natural Gas
14% Coal
2% Renewable ( Solar/Wind/ Hydroelectric)
1% Oil
Pie Chart
Difference between a bar
graph and a line graph?
A line graph is a graph used to show change over time
Would we use a line graph in the following situations:
To show how many people like pizza in this class?
To show how much it rained each month this year?
Would we use a line graph to show when our birthdays are?
Our birthday does deal with time doesn’t it? (months/years)
A line graph shows change in time, so we would not use it for this type of
graph.
Line Graphs
Which should you use in science?
If you want to connect the
dots… do this one instead
What do you see?
Hint:
There are
3 images.
1. An old lady
2. A young
woman
3. A man with
a big
brown
mustache
Take a very close look at the 2 vertical lines.
Is one line is longer than the other?
They are the SAME length!
Compare this picture to the next
one…
What’s the difference?
What do you see?
Can you build these shelves?
What do you see?
Can you stack these blocks?
What animal do you perceive?
A Duck, Bunny, or BOTH?
This image contains a
picture and a word.
Do you see both of
them?
What do you see?
What images do you see?
Can you pick the tallest soldier?
They are all the same height!
What do you see?
The Landscape of Faces
Do you see the face on Earth?
How about now?