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What is a��control variable?

In a scientific experiment, a control variable is a factor that is kept the same for every test or measurement in order to make sure that the results can be compared fairly.In general, a variable is any factor that can change or be changed. So, for instance, if you’re measuring how effective a medication is, variables could include the amount of dosage, how frequently it’s taken, and the characteristics of each test subject, such as their age and weight. Variables are called variables because they vary, but the point of a control variable is that it doesn’t.In the context of scientific experiments, there are three different types of variables: dependent variables, independent variables, and control variables. Independent variables are the factors that you change. Dependent variables are things that are affected by the changes that you make—the results of the tests (which depend on the independent variables). Control variables are the factors that you do not change.For example, let’s say you’re trying to figure out which brand of plant food will help a sunflower grow to the tallest height. The dependent variable is the final height of the sunflower. The independent variable (the factor that you change) is the brand of plant food. There are a number of other factors that could impact the growth of the plant, including things like the amount of sunlight and the amount of water. To allow for a proper comparison of the results, these need to be control variables—they need to need to be controlled, or kept the same. This way, you can have a greater degree of certainty that the final difference in heights (the dependent variable) is due to which food each sunflower received (the independent variable), not differences in sunlight or water.Control variables are crucial to scientifically sound experiments and studies. A control variable is sometimes simply called a control. Both terms are widely used in science and statistics.