Can someone please differentiate USING EXAMPLES, controlled, control and constant variables for me please everything online is contradicting itself
Mod edit: changed title from all-caps
Hi there!
Controlled and constant variables are the same thing - the things you keep the same throughout the experiment. With the example of
Pasteur's experiment, controlled variables would include amount of broth used, type of flask used, temperature of the room, exposure of the flasks to sunlight etc.
The control is Pasteur's experiment is the flask (with broth) that is sealed. The control variable demonstrates what would happen if nothing is done to it, so you can then compare the results of your independent variables trials to it.
Another good (and easy) example of a control is when you are 'modelling'
Koch's experiment and looking at testing water or food samples.
During this experiment, you would leave an agar plate closed (never open it), seal it and incubate it. If your agar is pure, then nothing would happen. This is a control because nothing is done to it, so you compare the growth of bacteria / other microorganisms (which should be 0 on the control plate), to the other plates, that may have been streaked with a liquid or food product for example. This demonstrates that it's not the agar causing this microbial growth, but rather the substance you used on it.
Hope this helps!