Chpt8 how to do an experiment
Upcoming SlideShare
Loading in...5
×

Like this? Share it with your network

Share
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
459
On Slideshare
458
From Embeds
1
Number of Embeds
1

Actions

Shares
Downloads
0
Comments
0
Likes
0

Embeds 1

http://www.slideshare.com 1

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. L.O: students will review how toconduct controlled experiments. Do now: read your “cheat sheet”
  • 2. How to design a controlled experiment:
  • 3. Diet pill commercials use “before andafter” 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 atleast 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 DOESthe drug or the treatment. NOT get the drug or treatment!
  • 8. The two groups are compared to see IFthe drug or treatment REALLY works!!!!!!
  • 9. a good experiment must have a largenumber 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.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 13. You MUST be able to read a table and a graph!Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 14. You MUST be able to draw a graph from a data table!Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 15. In many experiments are looking for cause and effect relationships….Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 16. IF one thing CAUSES something ELSE.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 17. Experiments have independent variables and dependent variables:Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 18. independent variables are the cause.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 19. dependent variables are the effect.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 20. experiments are designed to see IF the independent variables causes the dependent variable to happen.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 21. in data tables: the independent variable is ALWAYS the first columnElapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 22. in graphs: the independent variable is ALWAYS the X-axisElapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 23. in graphs: the dependent variable is ALWAYS Y-axis.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 24. you must be able to draw conclusions from tables and graphs.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 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:Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 33. 1. Label the X-axis (ALWAYS the independent variable) label the Y-axis (ALWAYS the dependent variable)Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 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 01 32 73 124 205 306 45
  • 35. 3. Make an appropriate scale number line for the Y-axis. the unitsMUST 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 01 32 73 124 205 306 45
  • 36. 4. Accurately plot the points.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 37. 5. connect the points. Surround each point with a small circle, square or triangle.Elapsed Time (s) Speed Ms−1)0 01 32 73 124 205 306 45
  • 38. Now answer 50- 82.
  • 39. You probably WON’T have to draw abar graph BUT you must know how to read them!!!!
  • 40. Example: predict how much thiscountry’s population will grow in 2003.
  • 41. Now answer 83- 108
  • 42. Now: complete all the unfinished questions! Make me proud!