Doing Science: The Scientific Method

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Doing Science The Scientific Method

• Chapter 1-2
• Science 8

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• What are two types of research?

• Descriptive research
• Solve problems by observation
• Experimental research
• Solve problems by testing hypothesis through use
  of carefully controlled steps

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• List the steps of descriptive research.

• Research objective
• What you want to find out
• Research design
• How investigation will be carried out
• How data recorded and analyzed
• Bias
• Avoid bias
• Careful measurements
• Random samples

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• What are steps of experimental research design?

• Scientific Method
• Step-by-step approach to help scientists find
  solutions to problems

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• What are the steps of the Scientific Method?

• Purpose
• Hypothesis
• Experiment
• Analysis
• Conclusion

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• Step 1. Purpose

• What do I want to find out?
• Questions come from
• Reading an article in a book or magazine
• Interesting observations
• Thought about a scientific phenomenon
• Conclusions from another experiment

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• Purpose of the experiment should be specific
• Problem should be something that can be solved
  through experimentation
• What is the average number of seeds found in
  apples?
• Does the color of a surface affect its
  temperature?

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Practice Time

• Identify if the following questions would be
  appropriate for scientific investigation.

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• Which has more friesa large McDonalds French
  fry or a large Sonic French fry?
• What is the average number of pine cones on a
  branch of a pine tree?
• What happens if you do not eat breakfast?

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• Step 2. Hypothesis

• Idea to a solution for a problem
• Educated guess
• Based on knowledge/research
• This is what I think will happen.
• Written as an Ifthenstatement
• if is the part the scientist will change on
  purpose
• then is the result of the change

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• Hypothesis examples.

• IF fertilizer is added to a plant, THEN it will
  grow taller
• IF a player attends batting practice, THEN their
  batting average will improve.

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Practice Time!!

• Write a testable hypothesis for each of the
  following questions.

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• How does advertising for the aluminum can
  collecting week affect the number of cans
  collected?
• If we advertise for the aluminum can collecting
  week, then we will increase the number of cans
  collected.

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• How does the depth of a lake affect its
  temperature?
• If we measure the lake at different depths, then
  we will find that the temperature decreases as we
  get deeper.

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Step 3. Experiment

• Testing of the hypothesis to see if it is correct
• During an experiment, the following must be done
• Decide which variables and controls will be used
• Controlstandard that you apply to all parts of
  the experiment (does not change)

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• Independent variablevariable that you purposely
  change (whats being tested)
• Dependent variablevariable that is being
  observed (whats being measured)

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Practice Time!!

• Identify three possible variables for the
  following situations.

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• Determine length of experiment
• Repeat to verify results
• Be a good observer
• Measure exactly

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• Step 4. Analysis

• What happened during the experiment?
• Data is collected and observation are made during
  the experiment
• Numerical dataheight, weight, temp
• Verbal datawords to describe observations
• Any problems with the experiment are noted along
  with errors that occurred

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• Step 5. Conclusion

• What did I find out?
• Scientists will tell what was learned from the
  experiment
• Did the results confirm hypothesis
• Did the results deny hypothesis
• Are there any more questions to answer
• Brief statement that summarizes the key points
  and outcomes of the experiment