erinic
Posts: 1
Joined: Mon Aug 26, 2013 3:31 pm

### Science Fair

So my project is on whether or not more expensive golf balls are really worth it. I am having someone hit 3 different brands of golf balls 25 times each and then I'm going to see which brand had the farthest average. Then I am going to see if the prices of those brands reflected the distances. What would my independent variable(s) be? My control group?

theborg
Moderator
Posts: 350
Joined: Mon Oct 03, 2011 12:26 pm
Occupation: US Air Force Space & Missile Operations

### Re: Science Fair

erinic,

Welcome to science buddies and thank you for the question.

It is very important to pick your variables correctly. Independent variables are those that you as the scientist changes. A good experiment should have only one independent variable. The dependent variable are those parameters that change and are observable in response to the change in independent variable. There can be more than one dependent variable. In your case, the independent variable is ball cost. Your dependent variable is distance. The reason I suggest your independent be cost instead of ball type is that you could get 2 different ball types for the same price,and get different performance out of each, but not prove/disprove that cost=performance. In fact, to really prove this, i would get 3 differently priced golf balls but ensure they were from the same manufacturer (i.e. all made by ping). I might even take it a step further and get three ball types from the three top manufacturers to see if the performance difference between each price point is consistent across manufacturing. Also, i would ensure i got all balls from the same store location to ensure unit price markup was the same, or else find the manufacturers suggested retail price for each.

In this case you don't have a control group, per se. You are doing a comparison analysis across all ball types. Your control is measuring distance from a single location, such as from the tee.

For more info on variables, visit the project guide on this site located at the following link:

http://www.sciencebuddies.org/science-f ... ndex.shtml
Hope this helps.

theborg
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Superjkeith
Posts: 1
Joined: Fri Nov 28, 2014 6:21 pm
Occupation: Student

### Re: Science Fair

Idk what to put as the propose for my project and I can't switch projects because it's too late so I'm working on Getting a Bang Out of Breath Spray: Studying the Chemistry and Physics of a Small Explosion can somebody help me pick a question and a purpose for this project