4by12

Billiards Tip

Here’s a tip to improve your game.

First, some basic mechanics. When two objects collide, they exert force on one another. The line along which the force acts is perpendicular to the surface of contact (assuming there’s no friction). In the case of two billiard balls, this line of force connects the centers of the balls.

Now let’s say you’d like to know where you should hit that red ball to send it to the corner pocket. Draw a line from the pocket through the red ball’s center, and find its intersection with the sphere. Then get the cue ball to hit that intersection spot. If you do it accurately, you’ll score.

Note that this is an approximation that doesn’t take into account the friction between the balls, among other factors. But I found that under normal circumstances this is a very good approximation, and the method works well in practice.