Dependent and independent variables facts for kids
In an experiment, you often want to find out how one thing affects another. The things that can change in an experiment are called variables.
There are two main types of variables: dependent variables and independent variables.
The dependent variable is the part of the experiment that you measure or observe. It's the outcome that might change because of what you do. Think of it as the "effect" you are looking for. It "depends" on other things happening in the experiment.
For example, if you want to know how much light a plant needs to grow, the amount the plant grows is the dependent variable. It depends on how much light you give it.
The independent variable is the part of the experiment that you control or change on purpose. It's what you think will cause a change in the dependent variable. You choose the different levels or types of this variable to test.
Using the plant example, if you want to see how much light a plant needs to grow, the amount of light you give the plant is the independent variable. You can choose to give one plant a lot of light and another plant less light.
Here's another example: Imagine you want to see how stress affects a person's heart rate.
- The independent variable would be the amount of stress you create (e.g., giving someone a difficult puzzle). You control how much stress is involved.
- The dependent variable would be the person's heart rate. You measure this to see if it changes because of the stress.
Variables in Math
In mathematics, variables work in a similar way. When you have an equation, one variable often changes because of another.
For example, in an equation like y = 2x + 1, the value of y depends on the value of x.
- Here, y is the dependent variable because its value changes depending on what x is.
- x is the independent variable because you can choose any value for x, and then y will be calculated from it.
Sometimes, a dependent variable is also called a "response variable" or an "outcome variable." The independent variable might be called an "explanatory variable."
See also
In Spanish: Variables dependientes e independientes para niños
