Chapter 1 The Scientific Method The Scientific Method

Chapter 1 The Scientific Method

The Scientific Method • The Scientific Method – An organized way of solving a problem. • Importance – Provides an objective, standardized way of solving a problem. – Minimizes the influence of bias or prejudice.

How to Use the Scientific Method • The first step in the scientific method is to make observations and ask a scientific question or state a problem. – Be as specific as possible. • The second step is to collect background information. – Literature, peer feedback, prior research, databases.

How to Use the Scientific Method • The third step is to form a hypothesis based on your observations. – A hypothesis is a possible explanation. – Must be testable.

How to Use the Scientific Method • The fourth step is to test the hypothesis. – This is done by performing controlled, reproducible experiments.

How to Use the Scientific Method • Controlled experiments allow researches to isolate and test the effects of a single experimental variable. • • Variable - the factor in the experiment that can change. (temperature, light, time…) Only one variable should be tested at a time all other variables should be kept the same.

How to Use the Scientific Method • Identify the manipulated, responding and controlled variables. • • • Manipulated variable or independent variable the variable that is changed (light, temperature, time…) Responding variable or dependent variable - the variable that changes in response to the manipulated variable. Controlled variables - The variables which do not change.

How to Use the Scientific Method • Set up and run the experiment • • Control setup - Exposed to normal conditions. Experimental setup(s) - exposed to the manipulated variable.

How to Use the Scientific Method • The fifth step is to record analyze the data. • • Graphs, charts. The sixth step is to form a conclusion based on the data

How to Use the Scientific Method • If the conclusion supports the hypothesis. – Repeat the experiment in order to confirm the conclusion. • If the conclusion does not support the hypothesis – Repeat the experiment in order to confirm the conclusion. • If the conclusion continues to not support the hypothesis after repeating the experiment. – Revise the hypothesis and redo the steps of the scientific method.

Reproducing an Experiment • When a hypothesis is tested numerous times it may become a theory. – A well-tested explanation. • A theory can become a scientific law. – A scientific fact

Reproducing an Experiment • What if a scientist performs the same experiment as another scientist and the results do not agree? – Error in the first experiment. – Second scientist did not correctly follow the procedure or duplicate the experiment. – First scientists results due to chance. – Second scientist introduced a second variable.

Possible Errors When Applying the Scientific Method • The hypothesis may not be specific enough. • Errors in collecting data. • Errors in analyzing data. • Mathematical errors. • Experimental errors. • Procedural errors.

Summary • Make observations and ask a scientific question or state a problem • Background research. • Form a hypothesis. • Test the hypothesis. • Record analyze the data. • Form a conclusion.

Clicker Question • When performing a controlled experiment it is important to A. Test many variables at once. B. Test two variables at once. C. Test only one variable at a time.

Clicker Question A. The 50 customers in group A B. The 50 customers in group B C. Mr. Krabbs is the control group. D. The gas is the control group.

Clicker Question What is the independent and dependent variable? A. The independent variable is the amount of gas and the dependent variable is the new sauce. B. The independent variable is the new sauce and the dependent variable is the amount of gas C. The independent variable is the new sauce and the dependent variable is the old sauce D. The independent variable is the old sauce and the dependent variable is the new sauce.

Clicker Question What should Mr. Krabbs’ conclusion be? A. The new sauce works. B. The new sauce does not work C. The results are inconclusive

Clicker Question What is a suitable hypothesis for this experiment? A. The dirt will make the plant grow faster B. Water with Miracle Grow will make the plant grow faster C. More sunlight will make the plant grow faster.

Clicker Question What is the independent and dependent variable? A. The independent variable is the dirt and dependent variable is the amount of plant growth. B. The independent variable is the amount of plant growth and the dependent variable is the dirt C. The independent variable is the Miracle Grow and the dependent variable is the amount of plant growth. D. The independent variable is the amount of plant growth and the dependent variable is the Miracle Grow.

Clicker Question Which of the following IS NOT a controlled variable in this experiment A. Miracle Grow added to the water. B. The amount of water C. The number of seeds. D. The amount of dirt.

Clicker Question A. Sunlight and the amount of water are controlled variables and should be the same for both plants B. There is nothing wrong with this experiment

Clicker Question A. The results indicate that the experiment did not work since Larry and Terry’s results did not show an increase B. The results indicate that the experiment did work since Gary and Barry’s results showed an increase C. The results are inconclusive due to the mixed results and the lack of a control group. D. The results indicate that the Super Snail Snacks work but only half the time.

Clicker Question What should Gary do next? A. Give up B. Test a different snack C. Remove the data for Larry and Terry D. Redo the experiment