When testing a hypothesis, scientists use controlled experiments, modifying one aspect of an experiment to test the hypothesis. In this tutorial, you will learn about dependent and independent variables in an experiment and explore how some variables are manipulated by the experiment. Experiments reveal that some variables react to certain factors and others do not, which is an important aspect of critical thinking. By analyzing experiments, you will be able to identify the independent and dependent variables in a scientific study.
This slideshow describes the two types of observations made during an experiment.