Has there been any test done on this? Example: A lighter cb striking a heavier ob that is twice its weight at half ball aim, what happens to both balls? Same as two balls of same weight except cb travels further and ob less (since it is heavier) ??
What happen when a lighter ball collides with a heavier ball
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This is in relation to sidespin. I am trying to find out if there is any change in direction of ob - maybe substantial throw?
If the cue ball is lighter, it changes the carom angle...whitey goes wider.
I feel the object ball cuts closer to the math angle since there is less collision-induced
throw.
I have some empirical knowledge of this because when I was young there was a cue ball
that was the same size but was substantially lighter....it had a green dot...
..it was known as the Macon Fast-Draw.
..played a few long sessions with this ball.
Interested in what the science guys have to say.
A lighter cue ball bounces off the heavier ball. A stun shot, for instance, would look like a draw shot. A draw stroke would bring that light CB back so fast you'd think it had a motor in it.
If there's just a couple of ounces difference, the OB will take off at what appears normal speed, but it's really slower than normal. That extra couple of ounces gets transferred from the OB to the CB, making draw a lot easier and follow less effective. If the weight difference is extreme, like a 2oz CB hitting a 6oz OB, it would probably be near impossible to cause the CB to roll forward beyond where the OB was resting, regardless of how much top spin you put on it.
An easy test of extreme weight difference can be done using a ping pong ball and a golf ball (or a foosball ball).
If there's just a couple of ounces difference, the OB will take off at what appears normal speed, but it's really slower than normal. That extra couple of ounces gets transferred from the OB to the CB, making draw a lot easier and follow less effective. If the weight difference is extreme, like a 2oz CB hitting a 6oz OB, it would probably be near impossible to cause the CB to roll forward beyond where the OB was resting, regardless of how much top spin you put on it.
An easy test of extreme weight difference can be done using a ping pong ball and a golf ball (or a foosball ball).
Yes, many tests. Standard collision physics apply.
So, if a lighter cb strikes a heavier ob at half ball aim intending to pot in the corner pocket (long rail to left and short rail to right). In a normal situation it will be a 30 degree (approx) and the ob making the pocket. In the lighter cb and heavier on situation, will the ob make the pocket, hit the long rail or hit the short rail?
I think you're right.
It will hit the pocket. The angle of the object ball departing the contact point will still be 30°. As PT posted earlier, there would be less throw due to the lighter CB, and the departing path of the CB would be at a wider angle than normal (because it'll kick back from the OB due to the greater mass of the OB).
For the record, it's no fun playing with a super light CB. I have one. Position play is tough due to the CB bouncing off of object balls instead of rolling through them.
Yes. See the info, articles, and video on the ball weight, size, and wear effects resource page.
Enjoy,
Dave
Dr. Dave can chime in.........cue balls in particular often can vary in weight as much as 11 -12 grams.
Pool balls are allowed (sanctioned) to vary as much as 1/2 oz & that applies to object balls & cue ball.
168 grams is what the object balls and cue ball averages in Brunswick Centennial pool ball sets and
the Aramith Measles cue ball is of compatible weight but cue balls can and will vary in weight and
pool balls that have seen lots of play over the years, even the weight and size can become reduced.
Matt B.
Pool balls are allowed (sanctioned) to vary as much as 1/2 oz & that applies to object balls & cue ball.
168 grams is what the object balls and cue ball averages in Brunswick Centennial pool ball sets and
the Aramith Measles cue ball is of compatible weight but cue balls can and will vary in weight and
pool balls that have seen lots of play over the years, even the weight and size can become reduced.
Matt B.
That is inline with my experience (although, OB weights, especially the 1-ball, can also vary from each other quite a bit). Here's a pertinent quote from the first article on the ball weight, size, and wear effects resource page:
To see how much ball weight can vary in typical conditions, I took an accurate digital scale to my local pool hall (“Match Ups” in Fort Collins, Colorado). I weighed the CB and randomly selected OBs (and the 1-ball specifically) in each of eight Valley bar boxes with the assistance and permission of the owners. (Thanks Mike and Nicole!)
The CB weights were fairly consistent with an average of 5.89 oz, a minimum of 5.78 oz, and a maximum of 5.93 oz. The OB weights were lighter (2-3 percent on average) and less consistent with an average of 5.75 oz, a minimum of 5.47 oz and a maximum of 5.89 oz. The lightest OB was a 1-ball, which makes sense based on the extra abuse it takes (but this could also just be coincidence). If the heaviest CB were paired up with the lightest OB, the percentage difference would be about 8%. Luckily, this is still much less than the 25% difference demonstrated with the pool and carom balls in HSV B.49. However, the weight difference effects in this article would definitely be noticeable with this particular CB-OB combination, especially to a good and observant player.
Regards,
Dave
In my opinion the toughest part of playing with a light cueball is the deflection get magnified.
Under the premise of your question, whether the object ball would hit the short rail or the long rail would depend on whether you were cutting the object ball to the left or to the right to the pocket. The proper way to pose the question would be to ask if the object ball would go short or long, because then which direction you are cutting it no longer matters.
In general the cue ball is light because it is worn down. If you shoot a smaller ball along the same line, it will cut the object ball more. On the other hand, if you somehow aim with the side of the cue ball on the pocket side of the shot, and you send the edge along the "correct" line, you will cut the object ball less.
Here are a couple of shots showing the difference between a light CB and a standard CB....
https://youtu.be/zbCVNarYOZM
https://youtu.be/zbCVNarYOZM
I did mention that long rail is to the left and short rail to the right. Hope that is clear enough.
Wow, very nice video of the lighter and smaller cue ball hitting bigger and heavier object balls. Is that you? You are a very very good player, as could be seen by your stance, bridge, confident and straight cueing action. Not a wonder why you won some tournaments.
The reason why I started this thread was not to see how the cue ball react, but rather how the object ball reacts. Thanks for the video. Much appreciated.
Thanks. I'm sure the object ball (when being hit by a light cue ball) will just move a little slower from the impact, and possibly with less collision-induced throw occurring. The angle of the shot wouldn't change unless the balls were different sizes, as Bob J. has already stated.
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