What Is A Control In A Science Experiment?

Developing a winning science fair project requriesIf we return to the hypothesis used in the
an in-depth understanding of the scientific method.previous section then a control experiment can be
One of the steps in the scientific method thatset up. Since the student will want to compare all
gives students the most trouble is theof the results to those that are based on copper
development of an experiment. This is becausewire conductivity, copper wire will be used in the
students often forget to develop a controlcontrol experiment.
experiment.Using the Control Experiment Data
What Is an Experiment?Students will want to start by completing their
An experiment is used in a science fair project tocontrol experiment first. The data that is collected
test the relationship between two variables. Thein this experiment will need to be kept separate
first variable is the dependent variable. This is thefrom the data collected in the test experiments.
variable that will be measured for change. TheIt will be used as a data baseline. All of the data
second variable is the independent variable. Thiscollected from the other test experiments will be
variable is the one that is manipulated. A goodcompared to that collected in the control
experiment will only deal with one independent andexperiment.
one dependent variable set. The goal of theStatistical analysis tools and formulas will be used
experiment is to identify a cause and effectto determine two things. First it will be used to
relationship between the two variables beingdetermine if there is a statistically significant
examined.difference between what the control experiment
For example, if the hypothesis for your electronicdata shows and what the test experiment data
science fair projects is "the most efficientshows. If there is a difference then correlations
conductor of electricity is copper" then you willwill be drawn. For example, in the case of the
need to set up an experiment that tests variouselectronics science fair project the correlations
types of materials for conductivity efficiency.may show that copper is not the most efficient
Your dependent variable in this case will be theconductor of electricity, or it may show that it is.
conductivity efficiency measurement and theIt is the student's main goal to use the control
independent variable will be the material that youexperiment data and the test experiment data to
test for conductivity.prove or disprove their original hypothesis
What Is a Control Experiment?Disproving a hypothesis is the easiest of the two.
In order to determine if the results of theAll you have to do is show evidence that the
manipulation of the independent variable produceshypothesis was false just once. However,
unique results a control experiment is required.students need to know that you can never really
The control experiment will be set up just like the"prove" that a hypothesis is true. When your data
test experiment, however, in the control thesupports your hypothesis you just add to the
independent variable will not be manipulated.likelihood that it may be true.