They are used to test theories and hypotheses about how physical processes work under particular conditions (e.g., whether a particular engineering process can produce a desired chemical compound).
For example, agricultural research frequently uses randomized experiments (e.g., to test the comparative effectiveness of different fertilizers), while experimental economics often involves experimental tests of theorized human behaviors without relying on random assignment of individuals to treatment and control conditions.
Francis Bacon (1561–1626), an English philosopher and scientist active in the 17th century, became an early and influential supporter of experimental science.
Antoine Lavoisier (1743-1794), a French chemist, used experiment to describe new areas, such as combustion and biochemistry and to develop the theory of conservation of mass (matter).
Because of the importance of controlling potentially confounding variables, the use of well-designed laboratory experiments is preferred when possible.
In the centuries that followed, people who applied the scientific method in different areas made important advances and discoveries.
For example, Galileo Galilei (1564-1642) accurately measured time and experimented to make accurate measurements and conclusions about the speed of a falling body.
On the other hand, an experiment that provides a counterexample can disprove a theory or hypothesis.
An experiment must also control the possible confounding factors—any factors that would mar the accuracy or repeatability of the experiment or the ability to interpret the results.
Experiments can raise test scores and help a student become more engaged and interested in the material they are learning, especially when used over time.
Experiments can vary from personal and informal natural comparisons (e.g.
Ideally, all variables in an experiment are controlled (accounted for by the control measurements) and none are uncontrolled.