Maximum Collision Induced English

[1 Pocket Ghost]

I don't usually post in the pool-physics-theorems threads....I leave that stuff to Bob Jewett, Pat Johnson, etc.......But over at onepocket.org, while a bank shot where you want to use maximum collision induced english was being discussed, a poster asked about adding self-applied spinning english to collision induced english.....I have an opinion re. this subject that he brought up, and answered him, and I thought I'd post it over here on az as well....That said, this is how I interpret/diagnose this type of ball interaction...it may be correct as to the laws of physics, or not - Bob Jewett and his posse, may give their input, lol.

Imo, the reason you don't want to use outside english/sidespin when wanting to have maximum collision induced english applied instead, is because the more sidespin you have, the more it will take away from and negate the collision induced english......Explaining further >>> To induce collision induced english you want as much firm, solid, 'grabbing' contact as possible to occur between the cue ball and the object ball - a non spinning cue ball will give you this, whereas a ball spinning with self-applied english will more deflect/spin off of the object ball when it strikes it, giving you less 'collision contact grab'.....And so that's why you don't want to use self-applied spinning english, when wanting to achieve maximum collision induced english.....An analogy that I personally think of is...let's say a guy is standing next to you and your goal is, with one firm hard push, to push him sideways as far as you can....well, I think you will be able to push him farther if your hands and arms are moving solidly straight-forward, then if your hands and arms were spinning like tops when you pushed him = (that would be your hands and arms having spinning english applied to them)

- Ghost

ps, hopefully my pal Pat Johnson doesn't see this...contrarian/science/physics geek that he is, I'm sure he'll dispute it..........and my other buddy, SJDick, wants to disown me, for joining, or conversing with the pool-science-physics gang........

pps, oh yeah, and by the way....this morning, the beard eaked out a curmudgeonly confirmation of my theory, lol.

 

[mikepage]

I don't usually post in the pool-physics-theorems threads....I leave that stuff to Bob Jewett, Pat Johnson, etc.......But over at onepocket.org, while a bank shot where you want to use maximum collision induced english was being discussed, a poster asked about adding self-applied spinning english to collision induced english.....I have an opinion re. this subject that he brought up, and answered him, and I thought I'd post it over here on az as well....That said, this is how I interpret/diagnose this type of ball interaction...it may be correct as to the laws of physics, or not - Bob Jewett and his posse, may give their input, lol.

Imo, the reason you don't want to use outside english/sidespin when wanting to have maximum collision induced english applied instead, is because the more sidespin you have, the more it will take away from and negate the collision induced english......Explaining further >>> To induce collision induced english you want as much firm, solid, 'grabbing' contact as possible to occur between the cue ball and the object ball - a non spinning cue ball will give you this, whereas a ball spinning with self-applied english will more deflect/spin off of the object ball when it strikes it, giving you less 'collision contact grab'.....And so that's why you don't want to use self-applied spinning english, when wanting to achieve maximum collision induced english.....An analogy that I personally think of is...let's say a guy is standing next to you and your goal is, with one firm hard push, to push him sideways as far as you can....well, I think you will be able to push him farther if your hands and arms are moving solidly straight-forward, then if your hands and arms were spinning like tops when you pushed him = (that would be your hands and arms having spinning english applied to them)

- Ghost

ps, hopefully my pal Pat Johnson doesn't see this...contrarian/science/physics geek that he is, I'm sure he'll dispute it..........and my other buddy, SJDick, wants to disown me, for joining, or conversing with the pool-science-physics gang........

pps, oh yeah, and by the way....this morning, the beard eaked out a curmudgeonly confirmation of my theory, lol.

Your conclusion is right. That is, if you are shooting at an angle that gives maximum collision-induced throw, then adding either inside or outside english will reduce the throw.

But I prefer to state the reason a little differently. "Grabbing" contact is not what happens here. That term, which implies the two surfaces move together at least briefly, implies static friction like you find when you get "skid" or "cling."

Throw is a different animal. It always involves two surfaces sliding across one another rather then "grabbing" one another like gears do.

CIT and SIT are two sides of the same coin. They're just different ways to get one surface to slide across another. Inside english increases the sliding speed, and outside english reduces it (and can reduce it beyond zero to get throw in the other direction.)

An important thing about achieving maximum throw (whether CIT or SIT or some combination) is that you stun the cueball into the object ball. If the cueball is not stunned, then the sliding has an up or down component, and some of the sliding force is wasted.

 

[Patrick Johnson]

1PG:
Pat Johnson ... contrarian

Am not.

pj
chgo

 

[Patrick Johnson]

Perfesser Page:
if you are shooting at an angle that gives maximum collision-induced throw, then adding either inside or outside english will reduce the throw

What is that angle? I'm guessing about half ball.

And if your cut angle is greater than the maximum-CIT angle (say 45 degrees rather than 30), I'm guessing that adding some outside english could increase throw?

pj
chgo

 

[mikepage]

What is that angle? I'm guessing about half ball.

Yes, pretty close

And if your cut angle is greater than the maximum-CIT angle (say 45 degrees rather than 30), I'm guessing that adding some outside english could increase throw?

pj
chgo

yes again.

There are a lot of interesting plots of these things on Dave A's website