What happened here?

[PhilosopherKing]

Fooling around, I banged a ball hard into the rail.

The cue ball and object ball both hit one rail and collided again, causing the object ball to very distinctly curve the length of the table and into a pocket.

 

[MitchAlsup]

Spin (other than directly in line with the direction a ball is rolling) is the reason balls curve as they roll across the cloth.
The physics was all worked out in the early-mid 1700s under the name Coriolis, a Frenchman of leisure.
The math takes the form of vector-cross-product and represents the conservation of angular momentun.

 

[Tin Man]

Fooling around, I banged a ball hard into the rail.

The cue ball and object ball both hit one rail and collided again, causing the object ball to very distinctly curve the length of the table and into a pocket.

When you shoot a firm follow shot at an angle with the cue ball you will see the cue ball curve. It slides along the tangent line for a short distance until the topspin catches and bends the cue ball forward. The more speed, the farther it slides before it hooks.

An object ball shot hard will slide across the felt for a bit but will pick up natural roll at some point. This is the same as if you put topspin on the object ball. So if it hits another ball it will bend with topspin the same as a cue ball would.

What makes your example even more dramatic is that the ball your object ball caromed off of (the cue ball) was also moving. This means it was actually kicked backwards of what the tangent line would be (had the cue ball been stationary) and I can see how that could exaggerate the arc.

Makes me want to try to set up a trick shot where this is needed. I'll get back to you if I think of something!

 

[PhilosopherKing]

When you shoot a firm follow shot at an angle with the cue ball you will see the cue ball curve. It slides along the tangent line for a short distance until the topspin catches and bends the cue ball forward. The more speed, the farther it slides before it hooks.

An object ball shot hard will slide across the felt for a bit but will pick up natural roll at some point. This is the same as if you put topspin on the object ball. So if it hits another ball it will bend with topspin the same as a cue ball would.

What makes your example even more dramatic is that the ball your object ball caromed off of (the cue ball) was also moving. This means it was actually kicked backwards of what the tangent line would be (had the cue ball been stationary) and I can see how that could exaggerate the arc.

Makes me want to try to set up a trick shot where this is needed. I'll get back to you if I think of something!

Thank you

 

[gregcantrall]

Object balls can pick up an incredible amount of spin from a rail. I have seen object balls sit spinning long after all balls stop rolling in a hard break shot in 9 ball.