Experimental variables are measurable quantities that can change during an experiment. In any physics experiment related to motion, there are three main types of variables that must be identified and properly managed:

1. Independent Variable

This is the variable that the experimenter deliberately changes or controls. It is the "cause" variable.

In motion experiments, the independent variable is often:

• Time (t)
• Distance (s)
• Force applied
• Angle of incline

2. Dependent Variable

This is the variable that is measured or observed. It "depends" on the independent variable. It is the "effect" variable.

In motion experiments, the dependent variable is typically:

• Velocity (v)
• Acceleration (a)
• Displacement

3. Controlled Variables

These are variables that are kept constant throughout the experiment to ensure a fair test. If these changed, they could affect the results unfairly.

In motion experiments, controlled variables might include:

• Mass of the object
• Surface type and smoothness
• Starting position
• Equipment used