[hannasanarion]

In your program, each of the balls starts with zero horizontal velocity. This is not analogous to real life, in which the droplets from the jug will have the same horizontal velocity as the jug at the moment they detached. They shouldn't fall straight down, they should follow a ballistic arc. I don't have the skills to set up a simulation of this right now, but I wouldn't be too surprised if the total of those ballistic arcs forms a straight line.

[SamBam]

You're totally right. Adding in the ball's horizontal speed makes the article's statement correct: you do have to accelerate the jug by g in order to get a straight line.

Corrected model: https://scratch.mit.edu/projects/805927382/