Physics question (toilet related)
 

The longest log post brought this physics question to mind.

OK, let's say you take a dump and there are x pieces. You flush.

Now, sometimes everything flushes. Cool.

But other times, there's a floater left over.

Regardless of the how big x is, it seems like x-1 pieces always get flushed, leaving just one piece floating.

What is the physics explanation for this phenomenon of x-1 pieces getting flushed the first time, regardless of the size of x?

Re: Physics question (toilet related)
 

You should cross post in SMP, you might get some science geniuses to comment.

Re: Physics question (toilet related)
 

I can't believe a post about crap just went totally over my head.

Whatever this rule is, I'm pretty sure it doesn't apply to the [censored] low-flow, water saving, non-poop disposing shitter that exists in my apartment.

Re: Physics question (toilet related)
 

I would bet it has to do with gas content in one turd over another. But I'm no expert on [censored] matters and don't even play one on TV.

Re: Physics question (toilet related)
 

[ QUOTE ]
I can't believe a post about crap just went totally over my head.

[/ QUOTE ]

Me neither. I can't believe that [censored].

Re: Physics question (toilet related)
 

[ QUOTE ]
I can't believe a post about crap just went totally over my head.

Whatever this rule is, I'm pretty sure it doesn't apply to the [censored] low-flow, water saving, non-poop disposing shitter that exists in my apartment.

[/ QUOTE ]

If you have a low-flow toilet, you can open the tank and shorten the chain on the diaphram just enough so that it stays down, then it will use the entire tank for each flush instead of 1/3 of the tank.

Re: Physics question (toilet related)
 

[ QUOTE ]
I would bet it has to do with gas content in one turd over another. But I'm no expert on [censored] matters and don't even play one on TV.

[/ QUOTE ]

I do not believe that accounts for the x-1 factor, though.

Re: Physics question (toilet related)
 

You may have just changed my life.

Re: Physics question (toilet related)
 

[ QUOTE ]
[ QUOTE ]
I would bet it has to do with gas content in one turd over another. But I'm no expert on [censored] matters and don't even play one on TV.

[/ QUOTE ]

I do not believe that accounts for the x-1 factor, though.

[/ QUOTE ]

A problem I have his that this ONLY happens at work for me, not at home or seemingly anywhere else, only work, and yes, always 1, probably about 85% of the time.

Re: Physics question (toilet related)
 

[ QUOTE ]
[ QUOTE ]
I would bet it has to do with gas content in one turd over another. But I'm no expert on [censored] matters and don't even play one on TV.

[/ QUOTE ]

I do not believe that accounts for the x-1 factor, though.

[/ QUOTE ]

Good point. It would account for the x-1 factor if it was always the first or last that had a higher gas content. I'm reaching here and won't be volunteering to study the dilema.

Re: Physics question (toilet related)
 

I've encountered multiple floaters. I think you need to generalize and/or revamp the x-1 rule diablo.

-SmileyEH

Re: Physics question (toilet related)
 

Chaos theory really.

Turbulent water flows are not predictable, even with the same action and volume each time.

Combine that with the variables of length, width, and mass of the logs, and there is lots of randomness there to take care of how often all of the shite goes down, let alone the number of time you have to flush until your skidmarks leave the likeness of Jesus on the bowl.

Regards,.
Woodguy

Re: Physics question (toilet related)
 

[ QUOTE ]
OK, let's say you take a dump and there are x pieces. You flush.

Regardless of the how big x is, it seems like x-1 pieces always get flushed, leaving just one piece floating.

What is the physics explanation for this phenomenon of x-1 pieces getting flushed the first time, regardless of the size of x?

[/ QUOTE ]

You been hanging with dcfrths lately?

Re: Physics question (toilet related)
 

I think this is the likely explanation. The first out is pretty compressed by the stuff that has been pushing down on it. The last out probably has a much lower density and hence can float. The cut off point for the stuff actually coming out will be around this critical floating density so the last bit of stuff will float. I imagine this critical point varies from person to person.

People who are constipated have such dense [censored] which is first out that it will also sometimes remain in the bowl after a flush. Not because it floats though, it's like a stone at the bottom of the bowl.

I'm fairly shocked that I'm going to submit this, but oh well.

Re: Physics question (toilet related)
 

[ QUOTE ]
I think this is the likely explanation. The first out is pretty compressed by the stuff that has been pushing down on it. The last out probably has a much lower density and hence can float. The cut off point for the stuff actually coming out will be around this critical floating density so the last bit of stuff will float. I imagine this critical point varies from person to person.

People who are constipated have such dense [censored] which is first out that it will also sometimes remain in the bowl after a flush. Not because it floats though, it's like a stone at the bottom of the bowl.

I'm fairly shocked that I'm going to submit this, but oh well.

[/ QUOTE ]

Sounds like a good theory to me, maybe I should ask my physics professor about this, see what he thinks.

Re: Physics question (toilet related)
 

[ QUOTE ]
I've encountered multiple floaters. I think you need to generalize and/or revamp the x-1 rule diablo.

-SmileyEH

[/ QUOTE ]

I have too, but I find that a single floater is FAR more common than multiple, even when the total number of pieces is large. Is that not your experience?

Re: Physics question (toilet related)
 

[ QUOTE ]
The longest log post brought this physics question to mind.

OK, let's say you take a dump and there are x pieces. You flush.

Now, sometimes everything flushes. Cool.

But other times, there's a floater left over.

Regardless of the how big x is, it seems like x-1 pieces always get flushed, leaving just one piece floating.

What is the physics explanation for this phenomenon of x-1 pieces getting flushed the first time, regardless of the size of x?

[/ QUOTE ]

Even toilets can only take so much [censored]. So the pheonomen is explained as X x size -x2 cubed-1 Logicallly leaving a piece behind. A toilet can only take X bits of [censored] so the better question is how much X can it take....

Re: Physics question (toilet related)
 

I have not encoutered this phenomenon.

Re: Physics question (toilet related)
 

[ QUOTE ]
Chaos theory really.

Turbulent water flows are not predictable, even with the same action and volume each time.

Combine that with the variables of length, width, and mass of the logs, and there is lots of randomness there to take care of how often all of the shite goes down, let alone the number of time you have to flush until your skidmarks leave the likeness of Jesus on the bowl.

Regards,.
Woodguy

[/ QUOTE ]

I work for a large well known toilet manufacter, and I can tell you that there is no "chaos theory" during the flushing of a toilet. We have approx. 4 phd's that concetrate on the flow of water during the flush of a toilet.

What's my job? I flush test these things. Not all the time, but that is what my main project is right now. We us all different types of media to test what a toilet is capable of flushing.

This seems like an exciting topic for OOT lately (human waste), so if you have inquiries as to exactly what this process is just ask. May seem like a boring subject to some, but I can tell you that watching a toilet being tested can be pretty damn exciting.

Re: Physics question (toilet related)
 

I hope this is for real. If it is, can you seriously provide some info on the single floater phenomenon?

Re: Physics question (toilet related)
 

razor, in your testing do you use various fake poos that you all create in the lab? animal feces? human?

Re: Physics question (toilet related)
 

[ QUOTE ]
razorbet, in your testing do you use various fake poos that you all create in the lab? animal feces? human?

[/ QUOTE ]

[img]/images/graemlins/mad.gif[/img]

Re: Physics question (toilet related)
 

what is it with the [censored] threads today?

maybe a diet with more fiber El.D, to keep that [censored] in log form.

Re: Physics question (toilet related)
 

[ QUOTE ]
razor, in your testing do you use various fake poos that you all create in the lab? animal feces? human?

[/ QUOTE ]

The closest thing that we use that represents a "log" would be miso. There is an independent lab that test ours and our competitors bowls using this, so we use it as well. We are currently using miso in a condom. Really. All of them are the same size so we just keep adding these "logs" until the toilet cant handle them anymore. Pictures?

Sponges are also used, all different sizes and quanities. Lots of toilet paper. Some dye exchange tests (how much wizz is left behind.

As far as the x-1 floater problem, I can check into that. My guess would be that the jet on the bottom of the bowl probably randomly hits these "floaters" sending them to the top of the water surface therefore not being disposed of before the end of the flush cycle.

Re: Physics question (toilet related)
 

I never knew so much went into the flushing of a toliet, pretty cool.

Re: Physics question (toilet related)
 

[ QUOTE ]
All of them are the same size so we just keep adding these "logs" until the toilet cant handle them anymore. Pictures?


[/ QUOTE ]

.. http://www2.odn.ne.jp/shokuzai/photo/Miso.JPG + http://www.vpul.upenn.edu/ohe/services/condom.jpg

sure why not?

Re: Physics question (toilet related)
 

Razorbet,
Do you live in the Sheboygan area?

Re: Physics question (toilet related)
 

[ QUOTE ]
My guess would be that the jet on the bottom of the bowl probably randomly hits these "floaters" sending them to the top of the water surface therefore not being disposed of before the end of the flush cycle.

[/ QUOTE ]

I thought the 4 phd's would make sure they could control "random" events in turbulent water?

Water turbulence, much like air turbulence, is extremely tough to predict, even in models like toliets, where the variables are somewhat controlled.

Regards,
Woodguy

edit: chaos theory was developed to help describe meteorlogical systems, and was quickly adapted to help decribe turbulent fluid systems under hydrolic pressure....a toliet would be similar.

Re: Physics question (toilet related)
 

[ QUOTE ]
[ QUOTE ]
razor, in your testing do you use various fake poos that you all create in the lab? animal feces? human?

[/ QUOTE ]

The closest thing that we use that represents a "log" would be miso. There is an independent lab that test ours and our competitors bowls using this, so we use it as well. We are currently using miso in a condom. Really. All of them are the same size so we just keep adding these "logs" until the toilet cant handle them anymore. Pictures?

Sponges are also used, all different sizes and quanities. Lots of toilet paper. Some dye exchange tests (how much wizz is left behind.

As far as the x-1 floater problem, I can check into that. My guess would be that the jet on the bottom of the bowl probably randomly hits these "floaters" sending them to the top of the water surface therefore not being disposed of before the end of the flush cycle.

[/ QUOTE ]

What Dom is to women, you are to excrement disposal.

Re: Physics question (toilet related)
 

[ QUOTE ]
[ QUOTE ]
My guess would be that the jet on the bottom of the bowl probably randomly hits these "floaters" sending them to the top of the water surface therefore not being disposed of before the end of the flush cycle.

[/ QUOTE ]

I thought the 4 phd's would make sure they could control "random" events in turbulent water?

Water turbulence, much like air turbulence, is extremely tough to predict, even in models like toliets, where the variables are somewhat controlled.

Regards,
Woodguy

edit: chaos theory was developed to help describe meteorlogical systems, and was quickly adapted to help decribe turbulent fluid systems under hydrolic pressure....a toliet would be similar.

[/ QUOTE ]

My theory probably explains why I test and record results. Fluid Mechanics is not my strong suit.

Re: Physics question (toilet related)
 

I was a physics major in college, sorta, so I feel that I'm equipped to answer this.

See, when I was 17 in high school, I was pondering this very question with a couple friends of mine. The city proved too distracting. As such, Michelle, Rhiannon, Eric, Erin and I headed off to the North Cascades, far from the distraction of toilets to come up with an answer.

Well, after a few days of pondering and bathing naked in a few alpine lakes and getting our nipples gnawed on by misquitoes, we met upon another couple, Sarah and Aaron. Turns out there were fishing in these lakes for halibut. No, they weren't having any success.

I gave them a few pointers, and in return, they promised to start pondering what we were pondering as well.

That night, we set up camp, the 7 of us, and had ourselves a real clam bake. I mean, like, we baked clams. As we were dining on said clams, a very very irate brown bear came out of the woods to see what we were eating.

Knowing what I know about bears, I knew that we shouldn't run. I tried to explain this to my newfound compadres, but alas, they were quickly out of earshot. So, I ran to catch up with them, to impart some wisdom.

I finally caught up to them after about 12 steps (the clams seemed to bog them down), but the bear had turned his attention from the clams to the nipple-gnawed nomads. I then had a flash of brilliance. I didn't need to out run the bears, I only needed to outrun one of my compadres, most likely Michelle, for she is Evan-esque in nature, and has the same stride length as a raccoon.

So we all kept running, bear included. Soon, unfortunately (well, fortunately for all of us full grown types), the bear caught up with Michelle.

Now, I need to be a little delicate with what happenened next. Michelle got devoured, almost whole. The bear was quite content with his find, and the rest of us scampered to safety.

And, that's when it dawned on me. Regardless of how many of us there were, if none of us were gnomes, only Michelle would get eaten. If it was two of us, only Michelle would be devoured. If there were 7 of us (which there were), again, only Michelle would get scrumptiously enjoyed. If there had been 15 of us, only one would be eaten.

I hope this clears it up.

My nipples itch.

Josh

Re: Physics question (toilet related)
 

[ QUOTE ]
Razorbet,
Do you live in the Sheboygan area?

[/ QUOTE ]

Check your PM.

Re: Physics question (toilet related)
 

I think you can explain this with statistics rather than physics. Lets say there is some limit of loggage that the toilet will normally accept in one flush. We'll say hypothetically this number is 4. Now lets say 70% of the time, the toilet can accept this many logs. 25% of the time, it can only accept 3 logs. 4% of the time only 2 logs. 1% or less of the time 1 log or less. We'll call this number X.

Now, lets also assume there is a similar distribution to the amount of loggage that is normally deposit by the user. Lets say, 70% of the time this number of 2 or lower. 20% of the time, its 3. 7% of the time its 4. 3% of the time its 5 or higher. We'll call this number Y.

Now, if you starded making random trials given those 2 distributions, you'll find that a vast majority of the time, X is greater than or equal to Y, so there is no remainder. When X is greater than y, it will only be a difference of 1 the vast majority of the time.

I guess what I'm trying to say is that your sample size is too small.

Re: Physics question (toilet related)
 

this just may be the greatest explanation to anything ever...EVER! If I may be bold enough to try and explain this in layman's terms...

sometimes your [censored] just floats

Re: Physics question (toilet related)
 

[ QUOTE ]
this just may be the greatest explanation to anything ever...EVER! If I may be bold enough to try and explain this in layman's terms...

sometimes your [censored] just floats

[/ QUOTE ]

It is the fiber content that determines whether the poo floats.

Considering ElD's steak intake, I'm quite surprised he's ever seen a floater.

Re: Physics question (toilet related)
 

I thought this was going to be a thread about Coriolis effects and toilets flushing different ways depending on whether you're in the northern or southern hemisphere. I'm pretty sure that's an urban legend - I'm pretty sure that whichever way the water inlets to the bowl point are going to be the main factor - but it shouldn't be too hard to round up some quick data either way.

As to your question, one thing that occurs to me is that the number of logs is probably not the significant variable so much as total volume of crap, which is going to be pretty hard to measure unless you want to mark where the water level is before and after the pause that refreshes. Maybe your toilet can handle a certain amount of volume, and the volume is more consistent than the number of individual pieces, thus it's always the last log that puts you over the top. This seems unlikely but it's one mechanism.

The other possibility I could imagine is that there is asymmetry in the process by which pieces are formed, such that the last one out has some special property (is smallest, least dense, etc.) That's all I've got right now.

Re: Physics question (toilet related)
 

[ QUOTE ]
I thought this was going to be a thread about Coriolis effects and toilets flushing different ways depending on whether you're in the northern or southern hemisphere. I'm pretty sure that's an urban legend .

[/ QUOTE ]

You are correct.

Re: Physics question (toilet related)
 

Excellent answer. Between benholio and Josh W, I bet we have this one nailed.

Re: Physics question (toilet related)
 

[ QUOTE ]
The longest log post brought this physics question to mind.

OK, let's say you take a dump and there are x pieces. You flush.

Now, sometimes everything flushes. Cool.

But other times, there's a floater left over.

Regardless of the how big x is, it seems like x-1 pieces always get flushed, leaving just one piece floating.

What is the physics explanation for this phenomenon of x-1 pieces getting flushed the first time, regardless of the size of x?

[/ QUOTE ]

Your sample size is too small.

What we should do is get a thousand monkeys and a thousand toilets and have them take a thousand dumps each.

Using this information, we will be able to create a shatistical model complete with proprietary poo-remainder prediction algorithm.

The end result will be plugged into the C.R.A.P. (Colonic Remainder Algorithmic Processor) and we will be able to use distributed networking to calculate the P.O.O.P. (Process Oriented Outcome Progression).

I wish I knew some more big words, but I kind of ran out of steam....

C+ execution at best methinks....meh

Re: Physics question (toilet related)
 

I can't think of a good way to word it, so here's my stream of consciousness:

Patrick's Theory of Quantum Toiletry

Let's say there are M discrete positions for your turds to fall into as they fall in line and go down the pipe. Now, you have some number N (N <= M for now) turds in the bowl. I believe your problem is that you're assuming that your turds take the first N positions. This may be true for sinkers, but the floaters actually take the last F positions (F <= N). Now, M is a function of the bowl volume and geometry, as well as turd geometry in extreme circumstances. However, the actual number of positions that go with each flush is a function of the flushing mechanism and the piping just below the bowl. Many American toilets have poorly designed flushing mechanisms and piping, which results in incomplete flushes which typically flush M-1 or even M-2 turd positions. So... even if you have N < M, you're still going to have a floater occupying the Mth position and not get flushed. Of course, if you have N > M, then you'll end up with N-M+1 turds remaining post-flush.

One problem with this theory is that if it were absolutely true, then you'd never get that one floater, since it'd always occupy the final position and never get flushed (I have had this happen though, or at least nearly - it once took me 8 flushes and some extra TP to weigh the floater down). I think it needs to be stated that there's some threshold where N is sufficiently small relative to M where this theory doesn't apply and everything goes down.