In an experiment, we can define 3 types of variables.
Independent variables: Are these ones that the scientist can control and modify, in this case, would be the kind of rubber for the tires.
Dependent variables: Are the variables that react to the changes in the independent variables. In this case, would be "how much lasts each type of rubber".
Controlled variables: Are all of these variables that also have an impact on the dependent variable, so we need to control them (fix them) so they do not affect the study of the independent variable.
So, for this particular experiment, to find controlled variables we need to think on what things do affect the durability of tires.
Some examples can be:
- The material of the ground where the tires are being tested.
- The temperature of the ground where the tires are being tested.
- The type of car where the tires are being tested.
- The speed at which the tires are being tested.
- The internal pressure at which the tires are being tested.
If you want to learn more, you can read:
https://brainly.com/question/17687509
