“Knowledge comes from asking the right questions.” THE SCIENTIFIC METHOD “Knowledge comes from asking the right questions.”

The Scientific Method A process used by scientists to find answers to questions or to solve a problem.

Write a Question that asks what you want to know. STATE THE PROBLEM Write a Question that asks what you want to know. EXAMPLE When a golf ball, a tennis ball, and a wiffle ball are dropped from the same height, which ball will bounce highest?

COLLECT INFORMATION Information may come from previous experience (observations) or from research. EXAMPLES Experience: Golf balls are heavier than wiffle balls. Experience: Wiffle balls are smoother than tennis balls. Research: Which of the balls are designed to bounce? Research: Which ball contains the most rubber?

FORM A HYPOTHESIS Make an educated guess about what the answer to the problem will be. The hypothesis should be based on the information collected. EXAMPLE Based on research the golf ball will likely bounce the highest because it is the heaviest of the three balls and it is designed to bounce.

Design and Perform an experiment to test your hypothesis. TEST THE HYPOTHESIS Design and Perform an experiment to test your hypothesis. EXAMPLE Materials 1 – tennis ball 1 – golf ball 1 – wiffle ball 1 – meter stick Procedure-(Steps) Drop each ball from a height of 1 meter. Measure the height of each ball’s first bounce. (Measure from the bottom of the ball.) Repeat steps 1 and 2 four times for each ball. Average the four trials for each ball.

ORGANIZE AND ANALYZE DATA The results of an experiment can be recorded in many different ways. Tables or charts are useful for recording data in an organized way. Graphs can be used to compare results. EXAMPLE Type of ball Avg. Height of bounce (cm) Wiffle 20 tennis 55 golf 71

WRITE A CONCLUSION Write a statement that compares the hypothesis to the data and answers the question stated in the problem. It will either prove or disprove the hypothesis. Results that do not support the hypothesis may lead to a new or revised experiment. EXAMPLE The data shows that when a golf ball, tennis ball, and a wiffle ball are dropped from the same height, the golf ball bounces highest with a height of 71 cm. This finding does support the hypothesis.

***POINTS OF EMPHASIS*** Always write in a scientific manner. Don’t refer to yourself by using words like I, me, mine, etc. All amounts and measurements should always be written in metric units. Multiple trials increase the reliability of the results. If you make a mistake, or error, you need to do the experiment again.

Questions You Need to Know!! 1. How do I know if my experimental question (Problem) is good? 2. What are variables? The answer to the question must be: Testable Measurable Repeatable Characteristics in an experiment that change or could be changed.

3. What is an independent variable? 4. What is a dependent variable? 5. What are constants? The factor that the scientist changes on purpose. The factor that responds to a change in the independent variable. Characteristics in an experiment that are kept unchanged in all trials.

6. What is a control? What is data? What are trials? A standard to which you compare your results. Information collected during the experiment. The number of times an experiment is repeated for each level of the independent variable.

8. What are quantitative results? 9. What are qualitative results? 10.How should I set up my bar graph or line graph? Results that can be measured in numbers. Results that are observations or descriptions. When labeling the x and y axis always label the x-axis (horizontal) with the independent variable, and label the y-axis (vertical) with the dependent variable.

11. Which type of graph should I use? Bar Graph: Used to show how the independent variables compare to each other. Line Graph: Used when you want to see how continuous changes to the independent variable affect the dependent variable over time. Pie Graph: Used to illustrate numbers as a percentage of a whole. Not usually used in scientific experiments.