What would be the control group in this experiment?

so we did this experiment in my science class and i dont know what the control group would be. we took three balls, a bouncy ball, golf ball, and a ping-pong ball. we had a meter stick and we dropped each ball three times from 10cm, 20cm, 30cm, all the way up to 100cm. and any idea what it would be? thanks|||Your science teacher appears to have neglected to give you some very important information. That's the definition of an experiment and of an observation.





In an experiment, you, as a researcher make some type of change to part of something which you are studying, while leaving the other part in it's natural/normal state (the control group). This could be something such as giving one group of plants a fertilizer, and not the other, or giving a group of people a drug while others get a placebo.





In an observation, you record data about your subject, but you don't make any changes (or change all groups equally, as in lifting the balls from their resting state to a specific height so they can fall and bounce). Since there are no changes made, there is no reason to have a "control". This is what you've done by measuring how high a ball would bounce when dropped from different heights - you didn't alter any of the balls, you just used them as they were. The only "change" that was made was the height from which you dropped the balls, but this "change" was made for all the balls equally.





Some other types of observations might be a comparison of attention spans by age of an individual, or what types of vegetation grow in different soil types. No "changes" are made by the researcher to to any of the subjects in either case, just the necessary information (attention span, plant identifications) collected and classified by age, or soil type.|||There is no control in this experiment - you are simply comparing the "bounciness" of three different types of ball.


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