1. Your parents tell you that you are not allowed to watch TV while doing homework. You claim that you do better when the TV is on. How do you prove to your parents that this is true?

2. Scientific Method

3. Steps in the Scientific Method
Observation
Hypothesis
Experiment
Data Collection
Conclusion
Retest

4. Observations Gathered through your senses
A scientist notices something in their natural world

5. Observations
An example of an observation might be noticing that many salamanders near a pond have curved, not straight, tails

6. Hypothesis A suggested solution to the problem. Must be testable
Sometimes written as If…Then… statements
Predicts an outcome

7. Hypothesis
An example of a hypothesis might be that the salamanders have curved tails due to a pollutant in the moist soil where they live.

8. A procedure to test the hypothesis.
Experiment
A procedure to test the hypothesis.

9. Experiment
Variables – Parts of an experiment. Changing these could affect the results.

10. Experiment
A good or “valid” experiment will only have ONE Tested or changing Variable

11. To be a Valid Experiment:
Two group types are required
the control group
experimental groups

12. Experimental Group
An experimenter changes one factor and observes or measures what happens.

13. Constants All other variables must be kept the same each time
Those factors are called Constants

14. Other Variables
The factor that is changed is known as the independent variable.
The factor that is measured or observed is called the dependent variable.

15. Control Group Controls contain all constants
Controls are NOT being tested
Controls are used for COMPARISON

16. Independent vs. Dependent Variable

17. Example of Controls & Variables
For example, suppose you want to figure out the fastest route to walk home from school.
You will try several different routes and time how long it takes you to get home by each one.
Since you are only interested in finding a route that is fastest for you, you will do the walking yourself.

18. What are the Variables in Your Experiment?
Varying the route is the independent variable
The time it takes is the dependent variable
Keeping the same walker throughout makes the walker a control variable.

19. One more thing… it is best to make several trials with each independent variable.

20. Data Results of the experimentMay be quantitative (numbers)
qualitative
(Quality or something observed with the senses)

21. Data
Must be organized
Can be organized into charts, tables, or graphs

22. Precision vs. Accuracy
Precision means that all measurements/results agree with each other.
Accuracy means that the measurement/result reflects the correct value.

23. Precision vs. Accuracy

24. Conclusion
The answer to the hypothesis based on the data obtained from the experiment

25. In order to verify the results, experiments must be retestable.

26. Solving a Problem 1) State Observations about the problem
2) Form a Hypothesis about the problem (if…then…)
3) Design an Experiment to test the hypothesis
4) Collect Data
5) Form a Conclusion

27. A Theory is a well-established explanation for scientific data
A Theory is a well-established explanation for scientific data. Theories typically cannot be proven, but they can become established if they are tested by several different scientific investigators. A theory can be disproven by a single contrary result.