0
votes
0answers
21 views

Strange Spurting of Water

Yesterday, I punctured the base of a partially drunken 50cl bottle of Badoit sparkling water with a compass (the one used for geometry). For someone reason, a stream of water started spurting out of ...
1
vote
0answers
58 views

Calculating PSI generated by water entraining air as it flows down a pipe

This is the concept used in a trompe. Basically, the idea is that if we allow water to flow down a pipe and if that pipe has inclined air intake orifices near the top where the water enters, then the ...
2
votes
2answers
55 views

Dynamic water pressure from flow and diameter

I've to test some fire hydrants and need to get the dynamic pressure. For that I know I can use a Pitot tube but... I don't have. After Googling a lot, I found two formulas allowing to compute the ...
4
votes
1answer
552 views

Why can I see my breath after I pop my ears?

I have this weird but reproducible thing that I can see my breath for less than a second even in hot/humid weather. The key to do that is to pop my ears - I have to do that often, it's like I'm on a ...
1
vote
1answer
29 views

Do different density objects in liquids affect net weight [duplicate]

I would test this but I have no tools to test it with. If I have a beaker of water and weigh it on a measure. Then I stick my fingers in the water (it doesn't over flow) does the weight change or ...
3
votes
0answers
44 views

How would water drain out of a sealed pipe?

While hiking through the Grand Canyon, I started wondering. Say we have a pipe for the purpose of transporting water across a canyon, with the bottom submerged in a pool of water. Like the blue line ...
5
votes
1answer
85 views

Titanic Question

I was reading this question: Was Titanic's captain's decision correct? @oakad commented about a Russian vessel keeping itself afloat by going in reverse, using hydrodynamic pressure to keep ...
3
votes
2answers
66 views

Why doesn't water in water barometer boil?

I have read that the pressure in a water barometer at the top of the water column is around 0.5 psi and at such low pressures water should boil at around ~26°C (Room temperature). [1] [2] How ...
0
votes
1answer
122 views

Calculation of pressure from flow rate of water

Anybody kindly help me to find how to calculate pressure in bar from flow rate. I have a pipe and from that I am transferring water at a constant flow rate of 5ml/min. At this flow rate, with a 0.5 cm ...
5
votes
2answers
160 views

Difference between weight of water and pressure of water

(I didn't even have a basic formal education in physics. I'm learning through the internet out of my own interest, so if there are any silly mistakes, kindly bear with and guide me through.) ...
2
votes
1answer
54 views

If a window in a plane cabin breaks will a bunch of water vapor form?

If a plane has some windows broken mid-flight (ie open) will the plane suddenly be full of water vapor because of the difference of pressure?
5
votes
3answers
291 views

Is there a depth at which a human body, with lungs full of air, will no longer float?

I was watching a special on divers who dove down hundreds of feet without tanks or gear. The show referred to a depth at which the diver was no longer buoyant and would actually sink, even with lungs ...
4
votes
1answer
562 views

Does the pressure increase under an upturned glass?

During my children's bath time we were playing with an upturned plastic jug filled with water and making some plastic divers float up inside the jug - see image. If one of the divers swam from A to ...
1
vote
2answers
341 views

What will happen if we put balloon in water tank in space

Imagine this. You have some object (let say barrel) and fill it with water. The water remains rather calm so it doesnt' spills out. Then we take a balloon filled with air and push it in that tank. ...
1
vote
1answer
318 views

Water Pressure Calculation for a volume of water at a given height

I'm looking to create a rain harvesting system. I have a 275 gallon IBC tote that is 48" x 40" x 46". I have an adapter for a 3/4 garden hose at the bottom of the IBC tote. I'm trying to figure out ...
0
votes
3answers
70 views

Upward bouyant forces?

When an object is submerged in a fluid (e.g., water), there is a pressure on the object due to weight of water by p=mgh, but why is there an upward buoyant force?
4
votes
3answers
144 views

Can one pump water without providing an external source of energy? [closed]

I have a farm situated right beside a canal through which we use to get water for our crops. I am not financially sound to buy an electric motor. The water is 15ft below the ground level. So can ...
3
votes
1answer
373 views

Does water turn solid under deep ocean because of high pressure?

I know that we can make water solid with high pressure, so I think water will be solid in the deep ocean? If that is true, the depth of the ocean would be limited because water will become ice? ...
3
votes
2answers
122 views

How come a whistling kettle starts whistling only when water boils, and not long before - due to hot air escaping under pressure?

A whistling kettle will start to whistle when the water boils and turns into a jet of steam which then exits the small aperture in the spout. But why doesn't this happen much earlier - when the air ...
0
votes
2answers
77 views

Can a submerged capsized vessel be turned into a sort of diving bell and propelled forward like a submarine?

I am writing a story set in the 17th century and have read accounts of such early submarines, however, not much detail is available. If some kid of weights/plummets are attached to the sides of the ...
0
votes
2answers
89 views

Why doesn't water start to boil in soils?

Consider the following two scenarios: I take a vessel filled with some water and evacuate the air, the water will (or rather can) start to boil; if the pressure in the vessel is << atmospheric ...
6
votes
3answers
1k views

Effect of water pressure on sinking objects

As I understand, water pressure increases as we go towards bottom of the ocean. So if an object* is thrown into water and it starts sinking with some speed, does the sinking object's acceleration ...
2
votes
3answers
207 views

How much energy needed to push a volume of water?

I am trying to solve a situation, where I'd like to know how much energy would be needed to push a mass of water out of a container. Here's an image to help understand: The water tank has a height ...
0
votes
2answers
290 views

Compression and expansion

Why is it that solids on compression [As in striking a hammer etc.] heat up, but liquids and gases on compression [Pressurizing liquids causes them to freeze or gases to liquify] cool down? Can ...
28
votes
7answers
4k views

Is it possible to “cook” pasta at room temperature with low enough pressure?

It is known fact, that boiling point of water decreases by decreasing of pressure. So there is a pressure at which water boils at room temperature. Would it be possible to cook e.g. pasta at room ...
0
votes
2answers
723 views

Physics of the inverted bottle dispenser

When you invert a water-bottle in a container, the water rises and then stops at a particular level --- as soon as it touches the hole of the inverted bottle. This will happen no matter how long ...
1
vote
1answer
380 views

Hydrostatic pressure?

What what I understand, hydrostatic pressure is the "weight" of the water pushing against objects. But if this is true, why is hydrostatic pressure perpendicular to the surface it acts on instead of ...
3
votes
3answers
371 views

Water Level and Pipe Widths

I ran into a bit of physics yesterday, and couldn't understand the physics at work. I've been scouring the Internet, but haven't found the answer yet. I'm guessing there's a basic principle I'm ...
7
votes
1answer
215 views

Why water wont leak out in this case? (Picture provided)

just curious why the water in the aquarium tank would not leak out as shown in the picture provided below? The question is in the red circle. The water level in the aquarium tank is definitely higher ...
2
votes
1answer
2k views

Estimate temperature and pressure of steam in a pot of boiling water

Suppose we have a pot of known dimensions filled to level L with boiling water on a stove, covered by a lid with a vent of known dimensions. Given the steady-state temperature of the stove (bottom of ...
3
votes
2answers
2k views

Why should fluids be confined for Pascal's Law to be applicable

When is Pascal's law about fluid pressure propagation applicable? Is it applicable to a closed circular pipe with a pump rotating the fluid, but not to a tub of water. Most statements require only ...
1
vote
2answers
567 views

Water pressure on slanted wall

Water pressure is simply $pgh/2$ for a vertical wall parallel to the depth of the water at exactly the half the water's depth. Suppose the wall is tapered (angled) slightly at around 2 degrees from ...
6
votes
5answers
763 views

Can a diver swim a short distance in great depths without being physically crushed by the pressure?

I recently saw "The Abyss". Does it make sense that they do dives in these depths (700m) with soft suits? Also - what is all the depressurization talk about? Why do divers need to depressurize long ...
3
votes
1answer
207 views

Does tapping at the side of a bottle prevent shaken soda from bubbling over?

Anecdotal evidence has it that a bottle of soda that was heavily shaken will not bubble over if tapped at the side multiple times. Yet I wonder: Has the tapping really any effect? Or could it be that ...
7
votes
2answers
504 views

Why water in the sink follow a curved path?

When you fill the sink with water and then allow the water to be drained, the water forms a vortex.. And then it starts to follow a curved path downwards by effects of gravity.. Why this phenomena ...
4
votes
3answers
423 views

Is it easier to pump water up or down?

I'm trying to gauge the strength of aquarium air pumps, for use in a vertical hydroponic farm. A curious question arose: is it easier to pump water upwards vertically, or is it easier to pump it ...
2
votes
2answers
22k views

Freezing point of water with respect to pressure.

I know when the pressure is reduced, the boiling point of water is reduced as well. But how does the pressure affect the freezing point of water ? In a low pressure environment is the freezing point ...
0
votes
3answers
725 views

Pascal's law: pressure of fluid at different locations

I know that's stupid question, but I'm really confused what my teachers says, so I need to check that theory. Here are just two ordinary connected containers, which are full of water. On grounds ...
1
vote
1answer
509 views

A water balloon in vacuum: does it boil?

If I put water in a vacuum it will boil. But what if I put this water inside a balloon ? I searched for answers and fount this video: http://www.youtube.com/watch?v=9q8F3ClUuV0 It seams that the ...
3
votes
2answers
380 views

Pumping water from a closed column. Will the column get empty or just circualte?

As a picture is worth a thousand words, here is my problem: It is a closed water column with a bit of air in the top section. If I run the pump and make the water flow from IN to OUT, Will the ...
4
votes
3answers
420 views

How can I keep a smaller water reservoir's water level at half available when being fed from a larger reservoir? [closed]

I'm trying to create my own ultrasonic humidifier. I ordered the misting part which works great but it only functions correctly in shallow water. So I'd like to feed from a large water reservoir to a ...
15
votes
3answers
889 views

Why don't I feel pressure on my body when swimming under water?

If I put a couple of lead bricks on my foot, there would be a definite sensation of a heavy, perhaps even painful, force. Calculating the pressure for $20 kg$ of lead over a $100 cm^2$ area of my ...
2
votes
1answer
867 views

Pump pressure required to fill water tower

I have a water pump at a distance of x meters from a water tower located h meters above the pump through a pipe with diameter d. I am not concerned with the exact value just want to make sure my pump ...
1
vote
0answers
85 views

Determining Water Level

Given a cylinder of a constant shape and size, how can the water level be calculated using the inside surface of the container? For instance, could the inside lining of the container be a pressure ...
2
votes
2answers
776 views

Will the siphoning effect help a system pump water upwards if the water's entry and exit points are at the same height?

I am looking to pump water from a pool up to a roof for solar heating (black plastic tubing) and then back into the pool with the original source water. Does the gravitational force of the water ...
3
votes
1answer
472 views

Pascal law with two connected cylinders filled with water, and 50kg stones at both their ends

If I have two connected cylinders filled with water, and 50kg stones at both their ends (pressing both ends of the water) how much weight do I need to add on one side so that one of the stones reach ...
1
vote
3answers
250 views

Water, can it break through temperature?

If water is heaten up to ridicilously high temperatures, is it possible for the atoms in the molecules to lose their bonds? And if it is possible, isn't this some kind of chain-reaction? Like you ...
1
vote
1answer
297 views

How would this rapid depressurization of water really behave?

An in-development game(Starbound) recently released a demo of their water physics. At about 39 seconds into the video, a volume of water in a container is released when the cap on the container is ...
3
votes
3answers
3k views

Why did my frozen water bottle explode when I opened it after it defrosted a bit?

Last night I filled a 20 fl oz bottle (http://www.thenibble.com/reviews/main/beverages/soft-drinks/boylans-mash.asp) with lukewarm water from my tap. I filled the bottle pretty much to the brim, ...
3
votes
4answers
500 views

Water to ice expansion in $1\textrm{mm}^3$ pit - pressure on the pit walls?

[EDITED] by mistake, the subject was regarding 1m^3 instead of 1mm^3. There should be a significant difference between the two... A 1x1x1mm pit filled with water is frozen at a slow rate (1K/minute). ...