Planning a Science Investigation

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Planning aScience Investigation
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Write a definition for the process you are
investigating.
Developing the Purpose
Deposition is the dropping off and building up of
bits of eroded rock carried by ice, wind, or
water.
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Brainstorm the factors related to your process.
List at least three factors or conditions that
you think have an effect on the process you are
studying.

• The rate of the waters flow
• The weight of the eroded particles
• The size of the eroded particles

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This is a photograph of the Colorado River.
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Narrow Your Focus
Choose the one factor from the list above that
you are most interested in studying.
The size of the eroded particles
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Ask a Question
Now, ask a question about the effect of this
factor on the process you are studying.
Does the size of the eroded particle affect the
location where it is deposited?
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Hypothesis
Make a prediction about what will happen to the
process when you change the factor in some
measurable way. Use If and then in your
hypothesis.
If the size of the eroded particles is increased,
then they will be deposited closer to the place
they were taken from.
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This photograph shows deposition at the mouth of
the Mississippi River.
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Is this a good hypothesis?

• Does it explain my observations?
• I have seen fields after a flood, and the
  bigger rocks and logs were left closer to the
  stream, while the smaller objects were left
  farther from the bank.

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Is this a good hypothesis?

• Is it testable?
• I can vary the size of the particles and
  measure the distance they have traveled from
  their starting point.
• Im not sure exactly how to measure the size
  of a piece of rock or sand.

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Is this a good hypothesis?

• Does this hypothesis correctly predict new
  findings?
• We wont know the answer to this question until
  we can observe a different location where
  deposition has occurred.

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Plan Your Experiment
Design a Model What will use to represent the
earths surface that is being changed?
I will use small rocks in a long tray to
represent the ground around a stream.
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Plan Your Experiment
Design a Model What will represent the factor
that you have chosen to investigate?
I will use two different sizes of rocks to see if
the size of the particle affects where it is
deposited.
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Plan Your Experiment
What measurements will you make before, during,
and after the investigation?
Before the investigation, I will measure the
sizes of the two different particles and the
volume of water. After the investigation, I will
measure the distance each size of particle
traveled from its original location to the point
where it was deposited.
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Plan Your Experiment
Draw a Diagram
Start
Meter stick
End
Catch basin
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Plan Your Experiment
List the materials you will need. Items from
Classroom Items from Home
tray small rocks--MF water container large
rocks--JG meter stick catch basin water
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Plan to Collect Data
Create a table that you can use to record the
data for your investigation.
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Perform the Investigation
Tip 1 Make sure you keep all of the conditions
of the experiment the same for each trial except
for one variable.
The only variable should be the factor you are
investigating.
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Perform the Investigation
Tip 2 You will have greater confidence in your
conclusions if you repeat the experiment.

• you can tell whether the results are similar.
• you can lessen the effect of minor errors by
  finding an average of your results.

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Record Data
Be Objective! It is very important to record the
data according to your plan, even if the results
are not what you expected.
Some of the most interesting scientific
discoveries were unexpected! Dont let your
expectations keep you from learning something new.
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Analyze Data
You analyze data by putting it into a graph and
discovering trends.
Did the smaller particles travel farther than the
larger particles? A graph will give you a good
picture of the results.
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Draw Conclusions
In the conclusion, you answer these questions

• Do the results of your investigation support your
  hypothesis?
• Did experimental error have a significant
  effect on your results? If so, what could you do
  to lessen the error?
• What questions remain unanswered?
• What new investigation would you like to
  perform?

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Happy Investigating!