Cueball Physics - The Force of the Cueball

Sharivari

AzB Silver Member
Silver Member
Hi AZB,

I just released a video that took me over 40 hours to produce. And because thats a lot of time for a just 12 minute long video I want to share it with as many players as possible.

And of course I want to know what you think of it, how I can improve my videos in general and what I am most interested in. Did you learn something new? I am asking because I don't only want to produce videos that are helpful for beginners, but also for experienced players.

So if you're interested in the cueball behaviour you should give this one a try :)
https://youtu.be/KL0W45AkNMo

Sharivari
 

Ralph Kramden

BOOM!.. ZOOM!.. MOON!
Silver Member
.
Sharivari.. Your YouTube videos are some of the greatest out there.
Not that there aren't other good videos, but yours rank as top notch.

.
 

sjm

Older and Wiser
Silver Member
Excellent job. Good material and clear, concise explanations.
 

bbb

AzB Gold Member
Gold Member
Silver Member
thank you for all you do to disseminate knowledge
i subscribe to your youtube channel.....:thumbup:
 

gogg

AzB Silver Member
Silver Member
The little graphic showing the action of cueball and object ball at the bottom is An especially nice touch as well...
 

9Ballr

AzB Silver Member
Silver Member
Great video.
Your videos are always top notch and very informative.
Thanks
 

Dave-Kat

AzB Silver Member
Silver Member
Information, graphics, production are top shelf. Thank you for your hard work Sharivari:thumbup:

-Kat,
 

spartan

AzB Silver Member
Silver Member
Good job and nicely produced video
Good for someone like me who isn't much good in physics :thumbup:
 

mikepage

AzB Silver Member
Silver Member
Hi AZB,

I just released a video that took me over 40 hours to produce. And because thats a lot of time for a just 12 minute long video I want to share it with as many players as possible.

And of course I want to know what you think of it, how I can improve my videos in general and what I am most interested in. Did you learn something new? I am asking because I don't only want to produce videos that are helpful for beginners, but also for experienced players.

So if you're interested in the cueball behaviour you should give this one a try :)
https://youtu.be/KL0W45AkNMo

Sharivari


Excellent!
 

jokrswylde

AzB Silver Member
Silver Member
Great video and congrats on the sponsorship from aramith and simonis. Hopefully this is just the beginning of a very fulfilling journey for you. I enjoy your work
 

Sharivari

AzB Silver Member
Silver Member
Thanks. Yes I hope so, too. I love this game so much so that the dream obviously would be to do that 24/7 and nothing else than just pool. I think anyone who plays pool can relate to that. Just such an amazing game that never gets boring.
 

MitchAlsup

AzB Silver Member
Silver Member
As one versed in Physics: you are using the word force improperly. In physics we have

F = M × a

A perfectly well defined definition of what the word "force" means.

The word you want to use is mostly "Spin" but occasionally you want to use the word "energy".
Energy contains both the forward rolling velocity plus the spin component carried by the rolling ball.

For example: a ball rolling at 1 foot/second will travel a certain distance
A ball traveling at 1 foot/second with side spin will travel a much greater distance.
The ball with sidespin has greater energy (in this case through rotational inertia).
 

mikepage

AzB Silver Member
Silver Member
As one versed in Physics: you are using the word force improperly. In physics we have

F = M × a

A perfectly well defined definition of what the word "force" means.

The word you want to use is mostly "Spin" but occasionally you want to use the word "energy".
Energy contains both the forward rolling velocity plus the spin component carried by the rolling ball.

For example: a ball rolling at 1 foot/second will travel a certain distance
A ball traveling at 1 foot/second with side spin will travel a much greater distance.
The ball with sidespin has greater energy (in this case through rotational inertia).

Once the ball leaves the tip, the force acting on the ball is the force the cloth exerts on it from friction. And that is only there when the ball is sliding (not rolling) on the cloth. He is showing that just by noting the direction of that force (cloth on ball), a number of apparently complex motions of the cueball suddenly make sense.
 

Bob Jewett

AZB Osmium Member
Staff member
Gold Member
Silver Member
... For example: a ball rolling at 1 foot/second will travel a certain distance.
A ball traveling at 1 foot/second with side spin will travel a much greater distance.
The ball with sidespin has greater energy (in this case through rotational inertia).
I believe that a ball with lots of sidespin will not go farther for a given initial speed than a ball without sidespin. The exception is if it hits a cushion and thereby translates the sidespin into linear motion. This is not too hard to test.
 

MitchAlsup

AzB Silver Member
Silver Member
I believe that a ball with lots of sidespin will not go farther for a given initial speed than a ball without sidespin. The exception is if it hits a cushion and thereby translates the sidespin into linear motion. This is not too hard to test.

Bob,

Consider that a ball hit with sidespin has energy in 2 directions, 1) the typical forward direction, and 2) the spinning direction.

After a short distance over the cloth, the side spin and the forward roll on the ball converge at the place the CB touches he cloth. The ball has forward roll, and also has side spin, If both the forward roll and the amount of sidespin were equal, at CB contact,
The roll axis on the CB is now at 45º with respect to vertical. The point of contact of the CB with the cloth now circulates from the bottom of the CB to the <say> leftmost side of the CB.

The rotational inertia of a ball rolling at such an angle is greater than the rotational inertia of a ball rolling naturally forward at the same speed but without sidespin.

Thus there is more "energy" in the CB and it will roll farther.
 

MitchAlsup

AzB Silver Member
Silver Member
Once the ball leaves the tip, the force acting on the ball is the force the cloth exerts on it from friction.

Ignoring air resistance;

And that is only there when the ball is sliding (not rolling) on the cloth.

The forward rolling CB still has friction while rolling on the cloth--just a lot less than before it accumulated natural forward roll.

He is showing that just by noting the direction of that force (cloth on ball), a number of apparently complex motions of the cueball suddenly make sense.

My only complaint was the misuse of the word "force" in conjunction with the physical explanation. Physics has a strict definition of what a "force" is.

And while the video was both entertaining and well executed, nicely demonstrating the effects. The word "force" is inappropriate in a physics context.
 
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