![ddaa08d06c[1].png](https://i.imgur.com/BjGyJR3.png "ddaa08d06c[1].png")
Well, /sci/? Which is it?
Fuck you and your easy stupid fucking question
>>8018092
If it's so easy why don't you tell us the answer?
>>8018088
all the exact fucking same
>>8018103
Lol, how do you figure that? C has more water pressing down on the same surface area. C is the highest.
>>8018088
Let me guess, is this another of the typical bait problems that rely on some ambiguity in the problem phrasing which guarantees discord among those who reply?
>>8018110
Pressure doesn't depend on the shape of the container. Whatever the shape or width, the pressure at any particular depth is the same.
>>8018111
It's not even that. The answer just seems sort of off when you don't think about it, meaning hordes of idiots will argue over it.
>>8018113
I can see why that's true for B and C because at any given point on the bottom, there is an identical vertical amount of water
But that's not true for A vs B or C, since for example at any point near the corners of A, there is much less vertical water pressing down on it
Shouldn't that mean A is a lower average pressure at the bottom?
>>8018113
If pressure is force/area, then the area of the bottom of the container is smaller and therefore a higher pressure right?
>>8018120
Water pressure isn't just vertical. That's a simplification used for sufficiently large bodies of water.
>>8018123
Pressure is a function of volume for fluids
>what is Pascal's law
>what is the hydrostatic paradox
As expected of /sci/.
>>8018125
I see
Since any % change in volume between the containers also means an equal % change in amount of water, IF they are filled to the same height, then pressure must be equal
>>8018120
No, pressure increases with depth, they all have the same depths so they all have the same pressure at the bottom.
The pressure acts in every direction, so if you have a larger width (like in c), it would increase the pressure on the sides, not bottom
>>8018134
>pressure increases with depth
but why?
Lets say you have a tiny container, and a huge one and you fill them both up
If the big one is 200% bigger than the small one, then it holds 200% more water. What causes the pressure to not be equal?
>>8018110
oh yeah
>>8018119
That way or another, it's just bait as I assumed. Posted not in the hopes of answering an actual question or inspiring a meaningful discussion, but to have people pointlessly argue in a circle.
>>8018130
I was wondering the same. There are times I wonder about the demographics in here.
>>8018145
Because pressure works as an integral of depth and force. Since gravity acts on all parts of the fluid equally, then it only makes sense that pressure makes sense at depth.
The reason why the container shape doesn't matter, let's take C for example, is because the container is a solid and doesn't transfer its pressure anywhere. Each part of the container is under the pressure of the fluid above it, and it stops there.
>>8018088
appeal of pressure is always perpendicular on vessel wall and of course it concerns all wall surface, not only the base.
[math]
p(h) = p_amb + rho_L*g*h
[/math]
now do your integral shit or think of a vesselshape which makes this way easier.
Anyone who thinks they aren't equal is a moron.
>>8018222
ok, my mathjax is terrible...
>/sci/ spacetime threads gets 300 replies all professing to be experts on relativity
>Nobody here knows even Pascal's Law
>>8018262
>knowing a law is better than building an intuitive understanding
>>8018346
Lurk more, for what?
To see that many posters on /sci/ are actually stupid enough to not know this?
inb4 "lel you posted again, too the bait!"
>>8018329
>"Classical mechanics? Mathematics? Who needs to know that? I became a physics expert simply by watching Black Science Man movies!"
>>8018222
so is the pressure higher in the center of that container?
C
>>8018381
Classical mechanics was disproven by quantum physics.
>>8018694
fuck you sci, now I read about pascals barrel and i doubting my answer now.
>>8018705
Not sure if bait.
Quantum mechanics is different than classical mechanics because different forces play larger roles at the quantum level.
Guys, think of the water as a pile of marbles, now think about the Gravitational Potential Energy of each marble in the container. Which one has the highest sum of total GPE?
>>8018362
to see what troll threads look like if you're so socially inept that you can't determine whether someone is serious or not.
>>8018088
>nobody has posted this yet
https://www.youtube.com/watch?v=aUW_8cWG7YA
fucking nerds
>>8018113
Okay then explain one thing you retard, if I put the containers on scale, which would exercise the most pressure on it?
Obviously A is the lightest, B in the Middle and C the heaviest.
So if the bottom of the container was in fact a scale, you want me to believe it woulf output the same weight for all 3?
This has to be b8.
>>8019024
>Implying some of the vertical force isn't acting on the walls and transmitted through the styrofoam, not the water
>Implying a cup breaks pascal's law
Water isn't compressible so there's no pressure on it!
>>8018088
Pressin' down on you, Pressin' down on me no man asked for
>>8018088
What about if the blue part is solid or more viscous?
>>8018088
https://en.wikipedia.org/wiki/Pascal's_law
discovered circa 1645
pls stop
>>8018088
Pressure =density * acceleration due to gravity * height or depth
All equal
>ITT people argue that a 2ft tall cone with a radius of 1 ft exerts is much pressure at the tip as a 2ft tall cone with a radius of a trillion ft that can hold all the water on earth
whats the coolest thing i could put in a a hpp machine that does 87000 psi
None.
>>8018088
Which one has 2 car loans, a mortgage, 50k in student loans, a wife, and 3 kids?
That's the one with the most pressure.
>>8019253
>What is weight vs pressure in the water
The cone itself- the structure of it- is what is exerting a higher pressure on the earth. At any depth in the cone, the pressure of the water is the same.
>>8019282
Are you dumb? They are all equal, therefore, none of them is the "greatest"
>>8018088
C, greater volume of liquid above to push down.
>>8018110
Imagine you have a really really giant dish with 1 inch of water on top. You cut a tiny hole on the bottom right in the center. Are you expecting it to shoot out like a firehose?
>>8018088
hydrostatic pressure isn't dependent on volume only depth
so d
>>8021430
Depends on your reference frame
>>8021435
Now think of the ocean. By your logic, I shouldn't be able to swim in it without facing extreme amounts of water pressure.
>>8021435
dude, are you dumb? the volume is greater, but the vessel's walls partially push up the water as well.
The pressure of a liquid is dependent only on depth, density and g.
They're all the same pressure. For those saying A is the most pressure, imagine if you connected the bottoms of all three with tubes. If A was higher pressure, it would force water into the other two cups, which doesn't make sense because the water level is the same in each cup
So, what happens if you step into the ocean, up to knee deep? Is all that massive billions of gallons of water at that depth going to crush your leg?
Think about that then answer the OP.
>>8018103
exactly, density*gravity*height
>>8021444
it specifically says at the bottom. The further you go the worse the pressure gets.
>>8021592
dude, that's because pressure only changes with depth. It doesn't matter if it's a cup of water or the ocean.
As long as they have the same density, if you measure the pressure at depth=10 cm in the ocean and in the cup, it's gonna be the exact same fucking number.
>>8021444
Try to swim at the bottom of the ocean.
>>8018088
A. Treat water like a shaped charge and you have an answer:^)
>people ITT legitimately trying to argue high school tier fluid mechanics
lol. i dare you contrarian faggots to do this in a crowded lecture hall.
>>8021661
>scroll up
>muh pascal is parroted
You could just invoke gravity, replace it with sand
>>8021679
>sand is a newtonian fluid
>>8018088
>>8021703
Shape C and E have lower pressures in their points P than all the others.
>>8022279
Am I on /sci/ to read this shit?
>>8022279
Pressure is about the masse of the fluid in those circumstances.
A B C D E F G H... Have the same water in the same proportion. Then the pressure is equal.
>>8022302
[math]p = \rho \cdot \mathrm g \cdot h + p_{ex}[/math]
In B and E, [math]h[/math], as such, the pressure is less.
>>8022315
>In B and E, h, as such
I meant to write, [math]h[/math] is less.
>>8022315
I'm going to kill myself for mix pressure and density
>>8022315
That's not how it works.
At all.
>>8022320
Then explain it, this is how I always understood it.
Pressure is the result of the weight of the water above and only directly above (due to gravity). Whatever it looks like on the side doesn't matter. Which is obviously why the pressure on the bottom of shape A and D is the same.
Are you saying that it's different for the inverse? That suddenly the weight of the water extends sideways?
>>8021442
what are you smoking?
Its likely C. However, because its not clear if its in a vacuum, its likely that theres even pressure from all angles, so B could potentially be correct or none.
>>8022340
>That suddenly the weight of the water extends sideways?
The pressure of the water always extends sideways.
>Pressure is the result of the weight of the water above and only directly above (due to gravity).
Nope. Unfortunately, I'm too tired to give you a clear answer, so have a fucking ugly one:
The pressure difference between two connected points is the (dot) product of the separation between the points and the force (per volume) being exerted on the fluid. (In less words, a path integral).
Therefore, in a fluid under gravity, two points at the same height have the same pressure, and a point below another point has a greater pressure, even if there's not a straight path connecting them.
>>8022374
Alright, thanks. I only had a shitty intro course to physics and a situation like this never came up.
>>8022340
>Pressure is the result of the weight of the water above and only directly above (due to gravity)
This is not only wrong, it's also inconsistent with your answer.
First of all, the question is asking for the pressure at the bottom of the container. So if pressure is from the weight of the water directly above the bottom, then why are you only looking at a single point on the bottom. Shouldn't you be looking at all the water directly above the bottom?
Second, your description of pressure is incorrect. It is not the weight of the water directly above, it is the *force upon the area* which matters. The water that is not directly above the bottom of the container still imparts a force on the bottom. A scale still measures the weight of your arms even if you spread them out past the area of the scale. Pressure is simply the force, or weight of the water, divided by the area the force is acting on. Because the weight of the water is partially dependent on the volume of the container, which is partially dependent on the area of the bottom, pressure is equivalent to density*depth.
>>8018130
These are counterintuitive, and the first is flat-earth science.
>>8019068
I guess you've never gone swimming.
>>8019253
Lel
>>8022340
I think it's the difference between how molecules interact in fluids and how anything structured by interlacing-non-bonded molecules interact or something
Which means water pressure is a lie
Just like someone said earlier, the pressure of a liquid is the same at any given depth below surface regardless of shape of the container.
>ITT people who forgot simple highschool science
What the hell are you guys still arguing here. Real answer is that pressure at the bottom is the same in every class. They all have same pressure from atmosphere above and hydrostatic pressure affects all directions. The physic's formula is:
[eqn] p = \rho g n [/eqn]
..where
p = pressure
[math] \rho [/math] = density of the fluid
g = gravity
h = depth
So, you all see, there is no difference in horizontal direction. Weight of the water above will even out in all directions because molecules push against other molecules.
New to thread here. I know liquid pressure is not dependent on the shape of the container, so I'm not trying to argue. I'm just trying to understand. I was just wondering about this scenario in pic related. What am I not considering here?
>>8022514
How will you fill the straw?
(hint: you will have to do it by applying a pressure exactly equal to the density of the water times gravity times the height of the straw uniformly on the whole ocean)
p = F/Area = rho*V*g/Area
for A: p_A = rho*V_A*g/Area
for B: p_B = rho*V_B*g/Area
for C: p_C = rho*V_C*g/Area
all the variables are same, except for volumes
V_C > V_B > V_A
so p_C > p_B > p_A
>>8022518
I'll just drill a hole, attach the straw, then pour water in from the top, then seal it off.
https://en.m.wikipedia.org/wiki/Pascal%27s_barrel
>>8022533
nice
>>8022528
>then pour water in from the top
Lifting that water 10 km would take quite a lot of energy, Anon.
>>8022315
Ok then. Try to find some thing resembling shape C and then put a hole in the top of the bottom segment. If there is no pressure then nothing should flow.
>>8022542
What does this have to do with the pressure at P?
>>8022514
Wouldn't that additional pressure from the straw even out with the ocean and rise the surface. So that you would have to rise the oceans surface to that 10km level before you would be able to top that straw.
>>8022562
>rise the surface
The entire ocean, including the surface, is sealed with waterproof, unexpandable material. It can not rise. There are no gaps or cracks.
>>8022514
The water would just spill into the ocean. If you consider the top of the straw to be your surface then you have no air there so the pressure equals pgh + 0 since no atmospheric pressure but the h of the water in the tube will equal h=atmo pressure divided by p and g . In other words let's say H is height of the tube itself above ocean and h height of the ocean. The pressure is pgh + pgH where pgH equals atmo pressure.
If you consider top of the ocean to be the surface then it's just pgh + atmo pressure which is exactly the same as pgh + pgH
>>8022577
What if we removed all the air from the atmosphere?
>>8022583
Then it just spills into the ocean and nothing happens.
>>8022584
So the pressure at P doesn't change? And the drinking straw becomes a vacuum?
https://www.youtube.com/watch?v=a01QQZyl-_I
>>8022595
If you remove air from the atmosphere everything is vacuum, you should ask yourself how would the inside of the straw become air in that situation. The pressure of P was atmo pressure before and now it's nothing at all.
>>8022627
>how would the inside of the straw become air in that situation
I never said it would become air.
>>8022546
The pressure is equal in all directions. If you remove the tops of the bottom segments, you won't have as much pressure in the up > down direction, and the pressure from below will be greater than the pressure from above, forcing the water out of the holes.
>>8022514
It's impossible to answer this question because everything is sealed.
You'd have to know the pressure in any point, so then you can use the vertical distance (depth) to find out the pressure in another point. For vessels that are open to the atmosphere, it's easy, because at h=0m, the absolute pressure is Patm, and from there on you can just use deltaP=density x gravity x depth to find the pressure at any point.
if the straw was open to the atmosphere, then P would be Pabs=Patm+ 10x1000 * density * 9.81 or Pgauge=10x1000*density*9.81.
Just so you can grasp what I'm talking about, imagine you had a 10.1km long straw and then you push the water down until the whole system is compressed enough and the straw becomes 10km long. The pressure at P is now obviously greater than if you hadn't pushed 100 meters and compressed the whole system.
So unless any part of the system is open to the atmosphere or you know the pressure anywhere, it's impossible to tell.
