| Term | Definition |
| Pendulum | A mass, suspended on a pivot point, free to swing |
| Controlled Experiment | All the variables are controlled except one, allowing the experimenter to observe the effect of that one variable on the outcome |
| Cycle | Any motion or activity that repeats itself |
| Variable | Anything you can change in an experiment that might affect the outcome. |
| Two-coordinate Graph | Displays the relationship between the independent and dependent variables in an experiment |
| Capacity | The maximum volume of fluid a container can hold |
| System | A set of related objects that work together |
| Independent Variable | The variable that is known and being tested by the experimenter |
| Dependent Variable | The variable that is not known before the start of the experiment and changes depending on the other variable |