1. L.O: students will review how to
conduct controlled experiments.
Do now:
read your
“cheat
sheet”

2. How to design a
controlled
experiment:

3. Diet pill commercials use “before and
after” shots as a side by side comparison to
show that the pills REALLY work!
When they ask if
you want to
“supersize
it”, say NO!!!!
before After!

4. Scientists conduct controlled experiments
as side by side comparisons too!!!!!!

5. A controlled experiment ALWAYS has at
least TWO groups: an experimental group
and a control group.

6. BOTH groups are IDENTICAL GROUPS…but
• only the (
).
• The
.
• Sometimes the control group is given a placebo (a
fake drug or a sugar pill)

7. Control group is identical to
Experimental group gets experimental group but DOES
the drug or the treatment. NOT get the drug or
treatment!

8. The two groups are compared to see IF
the drug or treatment REALLY works!!!!!!

9. a good experiment must have a large
number of test subjects, be repeatable &
take place for a long time!!!!!!

10. Characteristics of a good experiment:
1. Has both an experimental group and a control
group.
2. Has many many test subjects.
3. Is repeated many many times.
4. The experiment lasts for long time (weeks,
months, years…)

11. An old saying says: “A picture is
worth a thousand words”….

12. Scientists use graphs and tables
because they make complicated
data, easier to understand.
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13. You MUST be able to read a table and
a graph!
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14. You MUST be able to draw a graph
from a data table!
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15. In many experiments are looking for
cause and effect relationships….
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16. IF one thing CAUSES something ELSE.
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17. Experiments have independent
variables and dependent variables:
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18. independent variables are the cause.
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19. dependent variables are the effect.
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20. experiments are designed to see IF the
independent variables causes the
dependent variable to happen.
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21. in data tables: the independent variable is
ALWAYS the first column
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22. in graphs: the independent variable is
ALWAYS the X-axis
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23. in graphs: the dependent variable is
ALWAYS Y-axis.
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24. you must be able to draw conclusions
from tables and graphs.
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25. Now answer 1-20.

26. The scientific
method:

27. The scientific
method:
The scientific method is a method of
designing an experiment.

28. A well-designed experiment has the
following:
• A : written as a question.
:
• A : (a possible answer to the problem):
(NOT as a question).
( ),
( )
: what will be done to prove or disprove the hypothesis.
: the collected data.
: used to display and help interpret the results.
was the experiment , did the results support
or refute the hypothesis?

29. A valid experiment is one where the
data and conclusions support the
hypothesis.
The hypothesis was valid (correct)!

30. Now answer 21- 49

31. You MUST know how to draw line graphs.
There WILLLLLLLLLL definnnnnntellllly be
one on the regents!!!!

32. How to draw a line graph, using data from
a table:
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33. 1. Label the X-axis (ALWAYS the
independent variable) label the Y-axis
(ALWAYS the dependent variable)
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34. 2. Make an appropriate scale number line for the X-axis. the units
MUST be EVENLY spread out! (0,1,2,3,4 …or 0, 2,4,6,8…or
0,5, 10, 15…. Or 0, 10,20,30…or 0.0,0.5,1.0, 1.5, 2.0, 2.5….)
Elapsed Time (s) Speed Ms−1)
0 0
1 3
2 7
3 12
4 20
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35. 3. Make an appropriate scale number line for the Y-axis. the units
MUST be EVENLY spread out! (0,1,2,3,4 …or 0, 2,4,6,8…or 0,5, 10,
15…. Or 0, 10,20,30…or 0.0,0.5,1.0, 1.5, 2.0, 2.5….)
Elapsed Time (s) Speed Ms−1)
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36. 4. Accurately plot the points.
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37. 5. connect the points. Surround
each point with a small
circle, square or triangle.
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38. Now answer 50- 82.

39. You probably WON’T have to draw a
bar graph BUT you must know how to
read them!!!!

40. Example: predict how much this
country’s population will grow in 2003.

41. Now answer 83- 108

42. Now: complete all the unfinished
questions!
Make me
proud!