Data Analysis The scientific question answered was, “Does the length of a Pinewood Derby car’s body affect how fast the car will go?” The hypothesis was, “If the length of a Pinewood Derby car is shortened, then the speed will increase.” The independent variable was the length of the car, and the dependent variable was the time it took for the car to reach the bottom. There were many control variables, and some of them are the car used, the wheels used, the stopwatch used, and the ramp the cars were raced on. The control group was the Pinewood Derby car that had not been cut yet, and the experimental group was the two shorter car lengths. To perform the experiment, race the cars and record their times, then cut the car in half and make …show more content…
Because the weight was kept the same, that could not have had anything to do with the trend. The time decreases, which might have been able to do with the aerodynamics. All of the cars had a block of wood at the front, so that was kept the same. The wheels had to be moved closer every car, so the distance between the wheels might have made the smaller cars faster. The big car’s wheels were farther apart, and it might have scraped the track at the back, making it lose time. The wheelbase might have been why the smaller cars went faster. The results of the experiment make sense, because you need a hill to get the cars started, and the big car might have scraped the track. There could have been several extraneous variables such as stopping the stopwatch at a different point on the car, the tape making it weigh more, or if the stopwatch was not working properly. If one run had been at a colder temperature than another, then something could have happened to the wheels. The car may not have been let go of until after the stopwatch had started, or it could have been before. These influences could have caused the car’s speeds and times to be