2. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Jeremy wants to see if the amount of Wheaties he eats in the morning affects the number of points he makes in that day’s basketball game. While he changes the amount of Wheaties, he keeps using the same amount of milk. Amount of Wheaties Independent Variable

3. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Jeremy wants to see if the amount of Wheaties he eats in the morning affects the number of points he makes in that day’s basketball game. While he changes the amount of Wheaties, he keeps using the same amount of milk. Number of points Dependent Variable

4. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Jeremy wants to see if the amount of Wheaties he eats in the morning affects the number of points he makes in that day’s basketball game. While he changes the amount of Wheaties, he keeps using the same amount of milk. Amount of Milk Control Variable

5. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Christina wants to test whether the “smart pills” she recently ordered from the internet will actually improve her grades. She tries to keep the rest of her diet the same. Her grades Dependent Variable

6. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Christina wants to test whether the “smart pills” she recently ordered from the internet will actually improve her grades. She tries to keep the rest of her diet the same. Smart pills Independent Variable

7. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Christina wants to test whether the “smart pills” she recently ordered from the internet will actually improve her grades. She tries to keep the rest of her diet the same. Rest of her diet Control Variable

8. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Julia wants to see if the amount of water she gives her plant will affect its growth. She keeps the amount of sunlight the plant receives constant. The plant’s growth Dependent variable

9. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. Julia wants to see if the amount of water she gives her plant will affect its growth. She keeps the amount of sunlight the plant receives constant. Amount of sunlight Control Variable

10. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. University researchers are studying whether or not a student has breakfast every day affects his/her state test scores. During the study, they keep the number of students they are studying the same. The number of students Control Variable

11. But First - Review For each of the following experiments, state whether the variable mentioned is the independent variable, dependent variable, or control variable. University researchers are studying whether or not a student has breakfast every day affects his/her state test scores. During the study, they keep the number of students they are studying the same. Whether a student has breakfast Independent Variable

12. What is a Measurement? Measurement – describes a physical quantity with a number AND a unit

13. Common Measurements Quantity What it measures Metric Unit Tool used to measure it Length A distance Meters (m) Meter stick, ruler Mass How much matter there is Grams (g) Balance Volume Amount of space taken up by matter Liters (L) Graduated Cylinder

14. Measuring Mass 1. Put weighing container on balance. 2. Zero the balance. 3. Fill container with matter. 4. Read balance. Do NOT round.

15. Measuring Volume 1. At eye level, look at the surface level of the liquid. 2. Measure at the bottom of the meniscus, or curve. 3. Watch the lines! (Be careful when figuring out how many mL each line represents!) Each line in this graduated cylinder is 1 mL

16. Measuring Volume 1. At eye level, look at the surface level of the liquid. 2. Measure at the bottom of the meniscus, or curve. 3. Watch the lines! (Be careful when figuring out how many mL each line represents!) Each line in this graduated cylinder is 0.2 mL

17. Accuracy, Precision, Percent Error Accuracy – how close a measurement is to the actual value Precision – how exact your measuring tool is (usually has more numbers)

18. Accuracy, Precision, Percent Error Percent Error – shows how accurate a measurement is Smaller Percent Error = More Accurate

19. Example 1 Which trial has the most EXACT measurement? Trial 3 is the most precise Which trial has the smallest percent error? Trial 2 is the most accurate

20. Example 2 The actual volume of a 2 Liter bottle of soda is 2 L. However, when I measure the amount of liquid inside, I measure 1.9L. What is my percent error? Actual Value: 2L Your Value: 1.9L

21. Measurements Activity Read all directions CAREFULLY!!

22. Measurements Independent Practice Let me know if you have any questions!!

23. Unit 1 Vocabulary Review HypothesisTheoryLaw Independent VariableDependent Variable Control VariableModel Quantitative DataQualitative Data Graduated CylinderBalance Grams (g)Meters (m)Liters (L) AccuracyPrecisionPercent Error