http://www.ck12.org Chapter 1. Introduction to Physical Science
1.21 Scientific Experiments
- Define experiment.
- Contrast manipulated and responding variables in an experiment.
- Explain why other variables in an experiment must be controlled.
It’s exciting to roll down a skateboarding ramp, especially if you’re going fast. The steeper the ramp, the faster you’ll
go. What else besides the steepness of a ramp influences how fast an object goes down it? You could do experiments
to find out.
What Is an Experiment?
Anexperimentis a controlled scientific study of specific variables. A variable is a factor that can take on different
values. For example, the speed of an object down a ramp might be one variable, and the steepness of the ramp might
be another.
Experimental Variables
There must be at least two variables in any experiment: a manipulated variable and a responding variable.
- Amanipulated variableis a variable that is changed by the researcher. A manipulated variable is also called
an independent variable.