I-N-D-E-P-E-N-D-E-N-T variables, dependent variables, and constants

1. I-N-D-E-P-E-N-D-E-N-T variables, dependent variables, and constants Catalyst • What question is this data table answering? • What is one conclusion we can make from looking at this data table? ---------------------------------- • Write a hypothesis to answer this question: Why is hydro (water) power used so often? ---------------------------------- • Weekly Goal Write in complete sentences! Don’t talk during the Catalyst!

2. Today’s Agenda • Catalyst • Quiz grades • Variables Notes and Practice Time • I-N-D-E-P-E-N-D-E-N-T! • DEPENDENT • CONSTANTS • Exit Question HOMEWORK TONIGHT! UNIT TEST ON FRIDAY!

3. Quiz Class Averages 2CHEM 78 3BIO 73 4BIO 58

4. Objectives • By the end of today, SWBAT… • Identify independent and dependent variables, and constants in a scientific experiment

5. Experimentation • Key Point #1: A proper experiment always has an independent variable and dependent variable. • The purpose of an experiment is to test how changing ONE THING affects something else.

6. Green text = I’m teaching you a definition. Write it. Variables • Independent Variable: what causes the change we are measuring (acts independently) • Dependent variable: what gets changed (depends on other things) • Remember • Variables are always CATEGORIES of things: time, amount, frequency, size, type • Variables are NEVER specific things!!!

7. Teacher Models • Scientists have discovered something shocking: if you eat a lot of candy, then you will gain fat.  What is the independent variable? • Eat a lot of candy • Type of candy you eat • Amount of candy you eat • How much weight you gain

8. Teacher Models • Happy students learn more in school. So, Ms. S believes that starting school later would increase test scores. What is the dependent variable? • Starting school later • Happy students • Time that school starts • Test scores

9. NEW PROCEDURE! WHITEBOARDS!

10. Whiteboard Practice Goal: 90 s • When Ms. S says “GO!” • Send one member of your group to get whiteboardsand markersfor everyone (back shelf) • Send up another member of your group to get erasers– one for every two people (lab table)

11. Set Up Your Whiteboard #1 a. b. c. d. #2 a. b. c. d. #3 a. b. c. d. #4 a. b. c. d.

12. Whiteboards 1 • Ms. S believes that the more you study, the better grades you’ll earn. What is the independent variable? • Studying more • Amount of time you study • Grade earned • Type of test

13. Whiteboards 2 • Tyranea is always cold in class. She hypothesizes that if she wears many layers of clothing to school, then she will be warmer. What is the dependent variable? • Number of layers Tyranea wears • How cold Tyranea is • Temperature of the room • Tyranea will be warmer

14. Whiteboards 3 • Ms. Sanacore’s students want to test how easily bought off she is. Students who give her an apple get a “C.” Students who give her peanut M+M’s get an “A.” What is the independent variable? • Type of food • Apples and M+Ms • “A” on the report card • Report card

15. Whiteboards 4 • Jenika hates running, but loves listening to music. She believes that if she listens to music while running, then she will run more often. What is the dependent variable? • She will run more often • Listens to music while running • Frequency that Jenika runs • What Jenika listens to

16. If you’re having trouble… • 4 minutes • 26 mg of baking soda • Lifting weights every day • Medium t-shirts • Bullfrog • 16 candles • Never gets sick • Time to get dressed • Amount of baking soda • Frequency of lifting weights • Size of t-shirts • Type of frog • Number of candles • Degree of health WRONG RIGHT

17. Review • Ms. S believes that the more you study, the better grades you’ll earn. What is the independent variable? • Studying more • Amount of time you study • Grade earned • Type of test

18. Review • Tyranea is always cold in class. She hypothesizes that if she wears many layers of clothing to school, then she will be warmer. What is the dependent variable? • Number of layers Tyranea wears • How cold Tyranea is • Temperature of the room • Tyranea will be warmer

19. Review • Ms. Sanacore’s students want to test how easily bought off she is. Students who give her an apple get a “C.” Students who give her peanut M+Ms get an “A.” What is the independent variable? • Type of food • Apples and M+Ms • “A” on the report card • Report card

20. Review • Jenika hates running, but loves listening to music. She believes that if she listens to music while running, then she will run more often. What is the dependent variable? • She will run more often • Listens to music while running • Frequency that Jenika runs • What Jenika listens to

21. Guided Practice Worksheet • 8 minutes to complete independently (on your own, silently) • 3 minutes to compare answers • WORK HARD. It will help you with homework tonight.

22. Constants • Key Point #2: Everything but the independent and dependent variable must be kept constant. • Constant: variable we keep the same • If many different things change at once, we don’t know what causes the change!

23. Example • Let’s say we want to design an experiment to determine what causes GSP to win fights.

24. Cause and Effect! Number of fights that GSP wins

25. Answer in notes • Jay-Z hypothesizes that if he stops cussing, then he will sell fewer CDs because students like cussing. • What is the IV? • What is the DV? • What are the constants? • Remember, variables are CATEGORIES.

26. If Jay-Z stops cussing, then he will sell fewer CDs because students like cussing. • IV • Frequency that Jay-Z cusses • How often Jay-Z cusses • Amount of curse words in Jay-Z songs • DV • Number of CDs Jay-Z sells • How many CDs Jay-Z sells • Constant • Amount of money CDs cost • Number of tracks on each CD • How good each CD is

27. CLEAR YOUR WHITEBOARD!

28. Set Up Your Whiteboard IV = DV = Constant(s) =

29. Practice You want to know when in the year there are the most love bugs. Every night, you record how many love bugs you find outside. Time of year (season/month) IV = DV = Constant = Amount of love bugs

30. Practice Jenika needs to run a 6 minute mile to pass PE. She believes that if she runs every day, then she will be able to run faster. IV = DV = Constant = Frequency that Jenika runs Mile time

31. Practice Students of different genders were given the same puzzle to assemble. The puzzle assembly time was measured. IV = DV = Constant = Type of gender Time to assemble puzzle

32. If there are more students, then there will be more school buses. IV = DV = Constant = Amount of students Number of school buses

33. If the cost of beignets increases, then fewer will be sold. What depends on what? IV = DV = Constant = Amount each beignet costs Number of beignets sold

34. If the Saints sign more free agents, then they will win more games. IV = Number of free agents DV = Number of games won Constant =

35. Conclusion • A proper experiment always has an independent variable and dependent variable. • Independent Variable: what causes the change we are measuring • Dependent variable: what gets changed • Constant: variable we keep the same

36. Exit Question • Let’s say you want to figure out if drinking milk actually makes you taller. So you drink a glass of milk every day, and record your height every day. • What is the independent variable? • What is the dependent variable? • What are at least two constants? Write in complete sentences! Don’t talk during the Exit Question!