Answer: Ok, let's think our dependent variable like the position of a car with velocity of 50km/h, and our independent variable the time.
so, you can choose any time you want, and for each time, the car will be in a different position, so the position is a variable dependent of the time.
let's suppose you don't know the velocity of the car.
first you see the position at a time t₁ and the position is r₁.
then you see the position at time t₂, and the result is r₂.
here you changed the independent variable and observed how the dependent variable changed. And in this case, with the 4 numbers you observed you can obtain the velocity of the car.
So yes, you can call it an experiment.
