experiment

1. designing an experiment

2. A variable is something that changes.

3. 6 concepts of experimental design independent variable dependent variable constants control group experimental group repeated trials

4. independent variable the variable that is changedon purposeby the experimenter aka cause, stimulus, reason, manipulated variable, etc. This is the ‘’if” part of a hypothesis.

5. dependent variable the variable that responds aka effect(s), result(s), responding variable, etc. This is the ‘’then” part of a hypothesis.

6. constants all factors which areNOTallowed to change during the experiment

7. control group the group (standard) to which everything is compared

8. experimental group the group(s) being tested with the independent variable Each test group has only one factor different from the other test groups: the independent variable.

9. repeated trials the number of times the experiment is repeated The more times you repeat the experiment, the more VALID your results are.

10. chart IVCDV The is used to design an experiment.

11. iv dv constants fertilizer The variable (factor) that you will change is the independent variable. 0 drops 0 drops 0 drops These are the fertilizer amounts varied by the experimenter. 2 drops Plants with no fertilizer make up the control or control group. 4 drops 6 drops

12. iv dv constants fertilizer plant growth 0 drops The variable (factor) resulting from the independent variable is the dependent variable. 2 drops 4 drops 6 drops

13. iv dv constants fertilizer amt. of water plant growth These are the factors that must NOT change during experimentation. They must remain constant. type of soil 0 drops amt. of soil 2 drops type ofplant 4 drops type ofplanter 6 drops size of planter type of light location

14. 6 drops fertilizer 4 drops fertilizer 2 drops fertilizer no fertilizer

15. no fertilizer 6 drops fertilizer 4 drops fertilizer 2 drops fertilizer EXPERIMENTAL GROUP CONTROL What is this called? What are these called?

16. What are these called? CONSTANTS

17. What is this called? The plant growth that you observe here can be called . . . the results (of adding fertilizer) theresponse(to adding fertilizer) dependent variable the effects (of adding fertilizer) 0 2 4 6

18. amt. of water type of soil amt. of soil type ofplant type ofplanter size of planter type of light location What do you do if you want to test the type of soil instead of fertilizer? iv constants dv type of soil fertilizer plant growth fertilizer Fertilizer becomes a constant. Type of soil becomes the IV.

19. 5 spf 10 spf 15 spf 20 spf Take 7 minutes to design an experiment using the IVCDV chart to test the strengths of various sunscreen on aliens.

20. Evaluate the experimental design in the next two slides.

23. forming a hypothesis

24. V Chart

25. constants amt. of water type of soil amt. of soil type ofplant type ofplanter size of planter type of light location iv dv fertilizer plant growth + verb + verb Iffertilizer is addedto plants, thenplant growth will improve.

26. hypothesis V Chart Dependent Variable Independent Variable + verb + verb If independent variable+ verb, then dependent variable+ verb.