In a scientific method, what is the difference between a controlled variable and a dependant variable?

When you are in the lab, the controlled variable is the one that you can always change by will, in a direct way. The dependent variables are those that change when you change a controlled variable. For example, if you are measuring how much a spring stretches when you pull it, the controlled variable would be the force you apply to the spring, and the dependent variable is how much the spring stretches, i.e. the change in its size.

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