Here's why:

* Independent Variable: This is the variable that you change or manipulate in an experiment. You are controlling the velocity (how fast something is moving) to see what happens to the distance.

* Dependent Variable: This is the variable that you measure or observe. The distance traveled will depend on the velocity you set.

Example: Imagine you roll a ball down a ramp. You can control the velocity of the ball by adjusting the angle of the ramp. You then measure how far the ball travels.

* Independent Variable: Velocity (controlled by changing the ramp angle)

* Dependent Variable: Distance (measured after the ball rolls)