Scientific Method

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Scientific Method
Scientific Method
Step 1
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Pose a question or a problem. The research
question is the single most important part of
the scientific method. Every part of your
project is done to answer this question. The
research question is sometimes formed as a
statement and is called the "Problem" or
"Problem Statement."
Does temperature affect how many times a
cricket chirps?
Step 2
Develop a Research Plan


A research plan
involves finding
background
information about
your topic.
Why do crickets chirp?
Step 3
Hypothesis

A hypothesis is a answer or prediction
about the outcome of an experiment. A
hypothesis is written in an “If..., then...,
because...” statement
Example
If we increase the temperature of a crickets
environment, then the crickets will chirp more
because……..
Step 4
Design an Experiment
An experiment is a series of trials that are
done to support or refute (disprove) a
hypothesis.
Design a controlled experiment
• In a controlled experiment, only one condition is
changed at a time.
• All variables are kept constant except the one you are
testing.
How to Design an experiment with two groups.


The experimental group is the group that contains the
variable being tested.
The control group is the group that is the normal, or does
not contain the variable being tested.
Constants

Constants are factors in an
experiment that are kept the same
and not allowed to change.
Examples
1.
2.
3.
4.
5.
Age of crickets
humidity
Gender of crickets
Environment
Food
Two Types of Variables
Independent




variables that are
purposely changed or
manipulated in an
experiment
the factor that you wish to
test
usually expressed after the
word “if” in the hypothesis
could be thought of as the
“cause” in a cause and
effect relationship
Example
Change in temperature
Dependent




the factor you measure to
gather results
variables that may change as
a result of the independent
variable
usually expressed after the
word “then” in the hypothesis
could be thought of as the
“effect” in a cause and effect
relationship
Example
Number of chirps
Identify the Variables
independent
variable
1.
If a student chooses to not study, then they
will earn a poor grade.
dependent
independent
variable
variable
2.
If you drink Gatorade before a soccer game,
then you will score more goals.
dependent
variable independent
variable
3.
If you increase the mechanical advantage of
a pulley system used to move an object, then
the input force becomes less.
dependent
variable
2 Types of Data

Quantitative
data consisting of
numbers
Example
Sunlight leaves held on average 21
more pennies than leaves that
were in the shade.

Qualitative
data consisting of
verbal descriptions or
information gathered
using scales without
numbers
Examples
Leaves that were in the shade were
a lot stronger than leaves that
were in the sun.
Conclusion


Based on the Data collected during the experiment,
you can draw conclusions about the outcome of your
experiment. Was your hypothesis correct?
Some characteristics of a good experiment are:





Can be repeated by anyone and get the same results.
Have a large sample size.
Are peer reviewed.
Does not have to agree with the hypothesis.
Is objective (unbiased).
Mnemonic Devices
Q ueen - question
R achel - research
H opes - hypothesis
E very - experiment
C oward - collect data
G ains - graph/analyze data
C ourage - conclusion
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