Science Buddies: "Ask an Expert"

My son is doing a science fair project about the affect of different nose cones on the peak altitudes of model rockets. He is having trouble developing a name for the project. Does anyone have any ideas?

Variable Question
After testing three nose cones with the same model rocket engine my son decided to try a different engine to see if he would get the same results. He completed the same exact procedure with an engine that would make the rocket have a lower peak altitude. He is worried now that using the second engine will be considered another variable, but his intent was to have more reliable data. Is a certain shape of nose cone really the one that will have the highest altitude or is it just the one that will have the highest altitude with one particular engine? If more tests are completed to determine reliability of data are the changes considered variables? Theoretically he would really need to use every model rocket engine available with multiple rockets to truly generalize his findings. I'm not sure where the line comes down with only changing one variable in this situation.

Thank you
Hope

Hello HopePressler1,
The name of the project should be catchy and reflect the nature or the purpose of the project.
Some suggestions:
How High: The Effect of Different Rocket Nose Cone on Maximum Altitude
In the Height: The Effect of Different Rocket Nose Cone on Maximum Altitude

Feel free to look at more examples in the "Need catchy science project name" discussion locates in K-5: Life, Earth, and Social Sciences forum.
Also, the second engine data set counts as a second sample instead of a variable. The two data can be compared for a general hight trend of the cone. For example, one cone shape can results in a higher altitude than another cone shape for both engines. Then, there is evidence for the effect of the shape vs the maximum altitude.

More tests are acceptable as long all tests in that set receive the same treatment such as temperature. For example, you can test cone #1 and cone #2 five times on the floor; then, cone #1 and cone #2 five times on a table and cone #1 reaches a higher altitude every time despite the starting height, then there is evidence that cone #1 is doing better than cone #2.

He can only make a general statement for all rocket if he selects a simple random sample. But he can make a general statement with the group of rockets that use the same engine like his. This means that if his engine is hydrogen power, then he can only make a statement about hydrogen power rockets instead of nuclear power rockets.

Tell me if you have more questions.