For example if you wanted to see if plants would grow faster watered with sugar water or plain tap water, your constant control set up would be the plant watered with plain water. Since this is the "normal" condition with no changes it is the control setup.
Additionally there are two kinds of controls, positive and negative. Positive controls will have an indication or contain the specific substance that the test or instrument is used for. On the other hand, negative controls don't contain that specific substance or instrument. For example if you were testing the effects of aspirin on inflammation and you gave a group, 20 mgs of a placebo, that would be a negative control. Opposite to that would be a positive control, if you were testing the same thing and instead gave the group 20 mgs of the aspirin.
Experimental SetupIn short the part of the experiment that contains the variable is called the experimental setup. This is identical to the control setup except in one way. One change is made to the set up, this change is called the variable.In the example of the plants watered with tap or sugar water, the experimental set up would be the plant watered in the sugar water. Since this is the setup an which you are testing this, it is called the experimental (think of the experimental setup as a test) setup.
Experimental variableThe experimental variable is basically what you are changing between the control and experimental setups.
In the example, your experimental variable would be what the plant is watered with. So in this case, it would be the sugar water.
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http://answers.yahoo.com/question/index?qid=20080615165001AABZ33w
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Independent variable
When conducting experiments in science, it is important to have a baseline for knowing what happens if an independent variable is not present. In science, this is called the control experiment.
In a scientific experiment it is common to split your sample into (at least) two groups. Say you were to study the effect of a new drug on a specific condition, you would have a sample (a group of people with the condition in question e.g. breast cancer), and you would treat all members of the sample the same, with the exception that one group is give the actual drug, and the other group is given a "fake" pill. This fake pill is also called a placebo. The group that is given the real drug is called the experimental group, and the group that is give the placebo is called the control group. This setup attempts to ensure that any effect that is observed is caused by the drug (the experimental condition).
A control is a known setup for a given experiment that is known to have no effect on the outcome, that it will remain constant throughout all tests. It is part of a test group that does not change, so as to compare results in the end.
search: www.wikipedia.com
control setup
The control variable is the thing you keep the same and is everything that is not the independent variable. The Control Setup is there for the sake of comparison.
Independent variable
The experimental setup
Variable is, logically, something that varies, that is to say, is not constant over time. Controlled variable, in the control field theory, is a variable measure that is, or that needs to be, controlled. Like a voltage that you need to keep under 10Volts because some devices in the setup have an amplitude limitation. Manipulated variable is usually a measure, a variable that you can measure. For example, if you can measure the voltage in the experimental setup then you can manipulate it, like using it to power a device. Constant variable, i think this is not very correct, a mathematician's opinion might be needed. For me is a variable, thus something that is variable over time, that under certain conditions becomes constant, thus stops varying according to time.
control and experimental setup
If you test only one variable then you know that the difference in the experimental and control setup is that one independent variable. If you test more than one you will not know which one made the difference.
If you test only one variable then you know that the difference in the experimental and control setup is that one independent variable. If you test more than one you will not know which one made the difference.
only 1 parameter, or, variable, is manipulated at a time
were you setup your own experiment
EXPERIMENTAL SET UP * involves the set up that will allow you to investigate what you are interested to know. CONTROL SET UP * involves a set up that is exactly the same as the experimental, except the factor that you hypothesis to influence the results.
An experimental setup uses the independent variable.