Pool of Skittles

[Neosutra]

Because Skittles are quantum problem, amirite? Both quantum mechanics class are 5th and 6th semester, so yes, I can't answer the question on top of my head. I will sit down and think about it after my maths class if you want me to answer it that badly.

Actually, I didnt wiki anything, I worked the problem out like you asked (why the fuck would I wiki something on command like some little bitch of yours, I hope your not this stupid in real life). You are correct that I left off the dot above the x and y's, I should have just written d/dx(or y), but I assumed you already knew it was the derivitive since you went and had me fetch a basic physics answer for you.
And how about we play this game in reverse. Go fetch me this answer:

I gave you 2 posts to correct you mistake, you even argued I was right. Confusing position and velocity means you have no fucking clue what you're doing.

So you couldnt solve the problem? Guess your not a physics major.

Serious question though, as believe it or not I dont enjoy insulting you (well maybe just a little), what year are you in? I was trying to determine that by the last question I asked you. If you were Junior or Senior you would have probably known that off the top of your head, but my bet is your a sophmore. You have had some mechanics classes, and think the entire universe operates on newtonian physics and oversimplify every problem that way.

[Khamsin]

You have had some mechanics classes, and think the entire universe operates on newtonian physics and oversimplify every problem that way.

Regardless, I'm pretty sure skittles can be approximated well enough by newtonian physics, and is good enough for this thread.

Not that I agree with analyzing this using basic physics because you have a rather large system of many different objects pushing against each other, so any proper analysis using physics would involve so many repetitive calculations that it'd break tables and make people cry. That's why I went the geotechnical route, because that method is based on empirical data of measuring how various types of soils react to various stresses and strains, without having to break it down to calculations of force reactions of each individual particle. However, even that has issues because its assuming you have tiny rocks, not skittles.

[Charismatic]

Why would anyone walk on a pool of skittles instead of eating some and walking around it?

[Remyo]

Why would anyone walk on a pool of skittles instead of eating some and walking around it?

explain the sig

[evilbau]

Why would anyone walk on a pool of skittles instead of eating some and walking around it?

explain the sig

viewtopic.php?f=34&t=27039 nsfw

[Neosutra]

You have had some mechanics classes, and think the entire universe operates on newtonian physics and oversimplify every problem that way.

Regardless, I'm pretty sure skittles can be approximated well enough by newtonian physics, and is good enough for this thread.

Not that I agree with analyzing this using basic physics because you have a rather large system of many different objects pushing against each other, so any proper analysis using physics would involve so many repetitive calculations that it'd break tables and make people cry. That's why I went the geotechnical route, because that method is based on empirical data of measuring how various types of soils react to various stresses and strains, without having to break it down to calculations of force reactions of each individual particle. However, even that has issues because its assuming you have tiny rocks, not skittles.

Agreed.

I think atm we are all talking in conjecture and need to move to imperical data.

Who here has a swimming pool?

[Kaylia]

So you couldnt solve the problem? Guess your not a physics major.

Serious question though, as believe it or not I dont enjoy insulting you (well maybe just a little), what year are you in? I was trying to determine that by the last question I asked you. If you were Junior or Senior you would have probably known that off the top of your head, but my bet is your a sophmore.

1- We got a physics major who can't answer a simple mechanics question (you avoided it the one with spring and failed at double pendulum), and don't know kinetic energy equation

2- We got someone else who is halfway in the process of getting a major, and never had quantum mechanics class who can't answer a physics question.


Got a question, when you say you can approximate skittles as a fluid, does that mean pressure around you is constant? If it was, wouldnt bottom/up pressure also be constant?

You have had some mechanics classes, and think the entire universe operates on newtonian physics and oversimplify every problem that way.

Yes, and when you simplify it to fluid, I supose you are doing Relativity and Quantum physics? Am I right? Arguing that our skittles pool need to be analyzed with anything else than gravity force, friction and compression/deformation is stupid.

Not that I agree with analyzing this using basic physics because you have a rather large system of many different objects pushing against each other, so any proper analysis using physics would involve so many repetitive calculations that it'd break tables and make people cry. That's why I went the geotechnical route, because that method is based on empirical data of measuring how various types of soils react to various stresses and strains, without having to break it down to calculations of force reactions of each individual particle. However, even that has issues because its assuming you have tiny rocks, not skittles.

It would probably be easier to get data from 1 single skittle and apply basics physics before getting empirical data. I supose you coulddrop something in a glass filled with skittle to get an idea what would happen

Best way imo would be a study of material physics (no clue how to translate it in english), but it's very close from basic mechanics physics. You can approximate the situation with multiple linear equation.

[Khamsin]

It would probably be easier to get data from 1 single skittle and apply basics physics before getting empirical data. I supose you coulddrop something in a glass filled with skittle to get an idea what would happen

Best way imo would be a study of material physics (no clue how to translate it in english), but it's very close from basic mechanics physics. You can approximate the situation with multiple linear equation.

Well, the empirical data used to come up with the various coefficients used in geotechnical engineering (or civil engineering in general) are based off decades of research and observed data. You don't really need to do much original research in practice. Thankfully, it's not as bad in some areas of engineering as it is in others. Highway capacity/LOS and fluid dynamics come to mind in particular... both are so full of dimensionless coefficients and empirical equations it drives me crazy. However, in terms of structures, soils, and mechanics of materials, there are still some imaginary coefficients to look up, but for the most part the analysis is based on real physics (albeit boiled down and simplified to equations that are "good enough") and should be similar for skittles as actual soil. Keep in mind by "soil", organic fluff is excluded. Nobody builds on topsoil. The soil that such equations are based on are made up of rocks of various sizes, sometimes even bigger than skittles (i.e. gravel).

So the main thing to consider is what's the difference between a skittle and a rock, and how does that affect the outcome?

Also, if you wanted to try the experiment on your own, but can't afford to fill an entire pool with skittles, but at the same time don't want to make a container too small such that the proximity of the walls are influencing the outcome, here's something from my PE review course I took while I was studying for my license exam:

[attachment=0:1zard0lk]soilp.GIF[/attachment:1zard0lk]

This gives an impression of how the stress of a surface load is distributed through the soil. As you can see, not much load is transferred laterally, as the lines that shoot off to the sides are only 0.5% of the stress at the surface. Something that's roughly twice as wide as the width of your foundation (your shoes, in this case) and twice as deep should be enough such that the walls of the container "feel" only 8-10% of the stress at the surface. This is because it's being distributed throughout the soil and is not simply pushing straight down to the exclusion of all the particles at the side.