Scientific Investigation Practice © Jeffrey Campbell

Problem: What is the effect of the type of ball, a basketball and a soccer ball, on how high it bounces? A problem may be called a testable question. All problems should include both the IV and DV. © Jeffrey Campbell

Independent and Dependent Variables What is the effect of the type of ball, a basketball and a soccer ball, on how high it bounces? You control the type of ball You measure the height it bounces IV – type of ball DV – Height the ball bounces © Jeffrey Campbell

Levels of Independent Variables What is the effect of the type of ball, a basketball and a soccer ball, on how high it bounces? The change in your Independent Variable is sometimes called the “Levels of IV.” In our example, the levels are Basketball and Soccer Ball. © Jeffrey Campbell

Constant Variables Height the ball is dropped from Surface the ball bounces on Both of these things should stay the same so that the results are reliable. © Jeffrey Campbell

Hypothesis If a basketball and soccer ball are dropped from the same height, then the basketball will bounce the highest. Use the format: IF … say the IV being tested … then … predict the result. Some teachers may say: IF…IV…then…DV. © Jeffrey Campbell

Materials 1 basketball 1 soccer ball 2 Metersticks 1 Chair Duct Tape List any materials that might be needed. This list can be updated during the experiment if needed. © Jeffrey Campbell

Research Either provide research you have done, or say who you might consider an expert that you could go to for information. A basketball coach A soccer coach. © Jeffrey Campbell

Procedure 1. Gather Materials 2. Position a chair near a wall 3. Determine the height at which you will drop each ball and mark the spot with a piece of tape on the wall. 4. Have the tester stand on the chair and drop a ball from the marked height. 5. Have the spotter measure how high the ball gets after the first bounce. 6. Record data. 7. Perform three trials for each ball. © Jeffrey Campbell

Data Table How the type of ball affects the height it bounces (IV Label) Height Dropped From (meters) (CV Label) Height Bounced (meters) (DV Label) Trial 1 Trial 2 Trial 3 Average Basketball 2  1.3 1.2 1.4 Soccer Ball  1.1 1.15 1.1  1.12 Always include at least three trials AND an average column, a title, any units of measure, and write out the IV and DV labels. Do NOT just put IV, DV, and CV. © Jeffrey Campbell

Graph Always label your X & Y axis, provide a scale and a title, identify what the columns or lines represent, and draw the graph. © Jeffrey Campbell

Possible Errors Tell me something that might have gone wrong that could affect the results. During one drop, the soccer ball hit a meter stick when it bounced, which impacted the height of the bounce. © Jeffrey Campbell

Conclusion Tell me what the results of the experiment were, if your hypothesis was supported, and include any additional information you learned. In conclusion, I found that the basketball did bounce higher than the soccer ball. My hypothesis was supported. I think that the material used to make the basketball helped make it bouncier. © Jeffrey Campbell

Retesting Write a new testable question (or problem), that is similar to what you just did, but with one difference. PRO TIP: switch the IV with one of the CV’s. Which surface of gym flooring, tiles or hardwood, will cause a basketball to bounce higher? © Jeffrey Campbell