Final answer:
In an experiment, researchers manipulate the independent variable and measure its effects on the dependent variable. The independent variable is the only significant difference between the experimental and control groups, ensuring any observed effects on the dependent variable are due to this manipulation.
Step-by-step explanation:
In an experiment, the independent variable is manipulated by the researcher and its effects on the dependent variable are measured. The independent variable is also referred to as the manipulated variable because the researcher is actively changing it to observe the outcome. The dependent variable, on the other hand, is the variable that is affected as a result of the manipulation of the independent variable and is what is measured and statistically analyzed in the study.
In a well-designed experiment, the independent variable is the only significant difference between the experimental and control groups. This allows for a precise measurement of its effect on the dependent variable. Variables other than the independent variable that could influence the outcome are kept constant or controlled to ensure that any observed effects can be attributed to the manipulation of the independent variable alone.