Independent variables are values that can be changed in a given
equation or experiment. Think of an independent variable as your input.
An independent variable represents information that you put in to the
equation.

Dependent variables are values that result directly from the
independent variable. Ultimately, they depend on the independent
variable. Consider this example..

F = ma

When measuring the acceleration of an object, the mass does not change.
Therefore, it remains constant. The independent variable in this formula
would be force. Force can be changed, and a greater force results in a
greater acceleration.