Scientific Method

1. The Scientific Method involves a series of steps that are used to investigate a natural occurrence.

2. Scientific Method Problem/Question Observation/Research Formulate a Hypothesis Experiment Collect and Analyze Results Conclusion Communicate the Results

3. Steps of the Scientific Method 1. Problem/Question: Develop a question or problem that can be solved through experimentation.

4. Steps of the Scientific Method 2. Observation/Research: Make observations and research your topic of interest.

5. Steps of the Scientific Method What is the next step of the scientific method?!?

6. Steps of the Scientific Method 3. Formulate a Hypothesis: Predict a possible answer to the problem or question. The hypothesis is an educated guess about the relationship between the independent and dependent variables. *A hypothesis must be a testable prediction. Example: If the temperature in the classroomdecreases, then the students will become cold.

7. Steps of the Scientific Method 4. Experiment: Develop and follow a procedure. Include a detailed materials list. The outcome must be measurable **(quantifiable)**.

8. Steps of the Scientific Method 5. Collect and Analyze Results:. Confirm the results by retesting. Include tables, graphs, and photographs.

9. Steps of the Scientific Method 6. Conclusion: Include a statement that accepts or rejects the hypothesis.

10. Steps of the Scientific Method 7. Communicate the Results: Be prepared to present the project to an audience. Expect questions from the audience.

11. Steps of the Scientific Method So, what are all of the steps to the scientific method again? 1. Problem/Question 2. Observation/Research 3. Formulate a Hypothesis 4. Experiment 5. Collect and Analyze Results 6. Conclusion 7. Communicate the Results

12. What are variables? • Variables are factors that change in an experiment in order to test a hypothesis. • There are two main types of variables: 1. Independent Variable: The variable that is changed by the scientist; the ‘I control’ variable. **Will be on the X axis of a graph 2. Dependent Variable: The variable that might change because of what the scientist changes what is being measured. **Will be on the Y axis of a graph

13. REMEMBER! • Your hypothesis can TELL you what your variables are! • Ex. If I drink Mountain Dew before bed, then I will not sleep very much. • IV: Drinking Mountain Dew • DV: the amount of sleep

14. Practice • Your hypothesis can TELL you what your variables are! • Ex. If I drink Mountain Dew before bed, then I will not sleep very much. • IV: Drinking Mountain Dew • DV: the amount of sleep

15. Practice • If the teacher turns the temperature down, then the students will get hot in class • IV: Turning the temperature down • DV: Students becoming hot in the classroom

16. Let’s put our knowledge of the Scientific Method to a realistic example that includes some of the terms you’ll be needing to use and understand.

17. Problem/Question John watches his grandmother bake bread. He ask his grandmother what makes the bread rise. She explains that yeast releases a gas as it feeds on sugar. John wonders if the amount of sugar used in the recipe will affect the size of the bread loaf

18. Observation/Research John researches the areas of baking and fermentation and tries to come up with a way to test his question. He keeps all of his information on this topic in a journal.

19. Formulate a Hypothesis After talking with his teacher and conducting further research, he comes up with a hypothesis. “If more sugar is added, then the bread will rise higher.”

20. Independent Variable John is going to use 25g., 50g., 100g., 250g., 500g. of sugar in his experiment.

21. Dependent Variable In this case, it would be the size of the loaf of bread.

22. Control Group In a scientific experiment, the control is the group that serves as the standard of comparison. The control group may be a “no treatment" or an “experimenter selected” group.

23. Control Group The control group is exposed to the same conditions as the experimental group, except for the variable being tested. All experiments should have a control group.

24. Control Group Because his grandmother always used 50g. of sugar in her recipe, John is going to use that amount in his control group.

25. Constants All other factors stay the same so that any observed changes in the bread can be attributed to the variation in the amount of sugar.

26. A Little Practice with the Scientific Method The next slide is a Bart Simpson scenario. Read it carefully, and see whether you can answer the associated questions.

27. Bart Simpson believes that mice exposed to microwaves will become extra strong. He decides to perform this experiment by placing 10 mice in a microwave for 10 seconds. Each mouse was placed in the microwave for different lengths of time from one second to ten seconds. (do not do this at home, Bart is a misguided fictional character ). He compared these 10 mice to another 10 mice that had not been exposed. His test consisted of a heavy block of wood that blocked the mouse food. He found that 8 out of the 10 microwaved mice were able to push the block away. 7 out of 10 non-microwaved mice were able to do the same. • What was Bart’s hypothesis? • Identify the Control group. • Identify the independent and dependent variables • What might be some of the possible constants? • What should Bart’s conclusion be?

28. ANSWERS • Mice exposed to microwaves will be extra strong • The unexposed mice • Independent variable- microwaves Dependent variable- strength • Same block of wood, same food, time of day, approx same size mice, etc. • Microwave exposure does not significantly change the strength of mice.