Two Hydrogen atoms covalently bonded to one Oxygen atom. One of the more common compounds on the surface of the earth.

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How much entropy is produced in evaporating water due to irreversible evaporation towards equilibrium (humidity=100%)?

$dS=dH/T_{boil}$ for the increase in entropy by changing a phase at saturation ($T=373\text K$ for $p=1\text {atm}$ for water). However, water also obviously evaporates below boiling point when ...
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3answers
35 views

Is a flow of ionized water an electric current?

If $H_2O$ ions have a net electric charge and electric current is the flow of electric charge, can a stream of water ions be considered an electric current? If so, is it conceivably possible (not ...
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0answers
22 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 ...
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2answers
2k views

Why does a dish cloth absorb liquid better when it is damp?

Take a really dry dish cloth and try to wipe up some liquid you spilled on the kitchen counter. I will take up only so much of the liquid. Then try it with a damp cloth (or a wring out a wet one). It ...
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0answers
59 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 ...
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0answers
19 views

Sound vibrations for marine propulsion

I asked a similar question about bubbles making less friction on a mass moving through water, now I'm wondering of sound waves could do the same thing as supercavitation or possibly create it's own ...
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1answer
25 views

How big are soluted salts in drinking water?

I have just seen the TED talk Michael Pritchard: How to make filthy water drinkable where a device called LifeSaver bottle that filters particles that are bigger than 15nm out of water. I have heard ...
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2answers
59 views

How can water be liquid and gas in the same environment?

Think about it. If there's water in a gaseous form, how can there also be water in a liquid form? The gaseous water would have to have more energy than the liquid, but if it's the same temperature, ...
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1answer
13 views

What could be added to tap water to reduce air bubble formation on a submerged object?

Submerge your hand in a bucket of water. Some air bubbles appear immediately and others add to the surface of the hand over time. Is there anything that could be added to the water to reduce the ...
4
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1answer
67 views

What would happen if one drank only D2O for a long time? [closed]

Would it be lethal ? Would you gain 10% of your body weigth ?
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1answer
51 views

Phase diagram of water v/s other substances

Why for water increase in pressure decreases solidification temperature? The fusion curve of water is not same as that of other substances and for other substances specific volume increases during ...
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0answers
31 views

How big could a bubble of air and water be in zero gravity? Assume air surrounds and fills a bubble of water

I am designing an all water planetoid for a new science fiction novel I am writing. The Planetoid is a spherical bubble of water filled with air, and covered by a sufficiently thick atmosphere to ...
6
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1answer
232 views

Steam above meal

When I fry something on the pan and the fire is big and intensive (the flame over the pan), there is no stean above the pan or just a little. But when I turn off the fire, suddenly the steam appears, ...
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2answers
57 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 ...
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2answers
78 views

Which dumplings will be more salty?

There are two identical pots filled with different amounts of water (one has more water, the other one has less). The same amount of salt has been poured to each pot. The same amount of dumplings has ...
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2answers
39 views

Why is it that in a warm shower water feels hotter near the head?

When the water first hits your body, it feels warmer than when it streams down towards your feet. I realize that part of this is due to the water cooling down by dissipation to the surrounding as it ...
4
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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 ...
3
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1answer
37 views

What is the best angle to see water

Sometimes when I clean my house, I miss some of the water since it seems invisible, but when I stand in different angle from the water I can see it clearly, whereas some angles offer partial ...
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2answers
53 views

How does the temperature in a bucket of water with ice change over time?

I'm curious what happens to the temperature of the water in a bucket of water with ice in it. Let's start with a bucket with just ice in it, and we add water, in a room which is room temperature. It ...
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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 ...
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1answer
41 views

How does underwater sound sound?

I have been thinking about underwater sounds (i.e. sounds produced and recorded underwater), what exactly the water does, and how to emulate this effect. Imagine a sound played underwater (e.g. from ...
3
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0answers
45 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
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1answer
84 views

Why is a white cloud formed in the hot water from the pot when salt is added?

Why is a white cloud is formed in the hot water from the pot when salt (NaCl) is added?
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1answer
71 views

Boil Water,The Fastest Way [closed]

Few days ago I had to boil water to cook for myself a meal, and then I wondered what is the fastest way to boil that pot of water , any suggestions?(of course I had like to get some formulas and ...
5
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2answers
860 views

Do all liquids boil in a vacuum?

Water boils at positive temperatures when put into a vacuum. Is this the case with all liquids, e.g. mercury?
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1answer
38 views

Is there an equivalent to wetness for air?

I was wondering if there was something equivalent to the property of being wet with water, but with air instead. For example, if I drop water on my shirt, I'll notice by its appearance and feel that ...
5
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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 ...
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1answer
31 views

Interaction of ocean waves and currents

I was on a small island recently near high tide. As the tide started to go out, a tidal pond emptied into the ocean through a narrow channel with a strong outgoing current. There was also wind on ...
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0answers
24 views

Floating subject on a surface of water

If We put a small floating object (penoplast granule) on a surface of water it performs spiral like movements and eventually sticks to a side of a vial. What physical forces are involved? I'm ...
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1answer
75 views

How many joules of energy are required to convert 1 liter of water into hydrogen and oxygen, theoretically? [closed]

I've been reading http://en.wikipedia.org/wiki/Electrolysis_of_water and other related questions on physics.stackexchange, but I fear I don't have a decent enough understanding of math and science to ...
5
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2answers
121 views

What does really attracts a water stream to a charged object?

I saw this video by Varitasium and I was not 100% sure about the third phenomena, a statically charged object attracting a stream of water, especially because he explicitly mentioned that it is not ...
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0answers
33 views

Water pump with a tap connected at its opening not pumping water when water is drawn from the pump before starting the pump [closed]

Please give your explanation in layman terms, without throwing any complex equations at me. We have a 5000 liter tank dug in ground and a water pump connected to this tank that draws water from it ...
6
votes
3answers
226 views

Is it faster underwater to go down without air or up with air?

So I had a very interesting conversation between me and my friends about this topic, but we could not find the answer. The Situation Lets say you are in a pool and you want to touch the bottom and ...
3
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2answers
69 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 ...
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1answer
80 views

Why do my ice cubes stick together?

When I put ice cubes in a glass of water, I find that sometimes they will stick together and form a sort of "bridge" between them as they melt. There is usually a visible line where one ends and the ...
2
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1answer
34 views

Erosion effect from Coriolis force in a South-to-North water channel?

Imagine we could build a channel (like those cool ones in some countries) but very, very long, parallel to a meridian (ie South-North direction).. The channel would contain water, which would ...
1
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1answer
138 views

How do heated showers/faucets work? [closed]

I'm not sure if this question is for Physics SE, but I'd go ahead and ask. I was wondering how the heated showers work (the ones with the hot and cold knobs). I have always been curious and this may ...
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1answer
128 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 ...
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1answer
80 views

Is a falling, perfect sheet of fluid possible to create?

This is a bit of an abstract question so I'll try explain this as best I can from the bottom up. I would like to know if it is possible to observe a sheet of fluid, much like a sheet of glass, ...
3
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2answers
104 views

Why do some hand dryers blow hot air?

I am not sure why some hand dryers are blowing hot air and not just air at room temperature. To me, hair dryers are just a way to dry one's hands using the same principle as when we shake our hands ...
7
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2answers
102 views

Practical (maybe naive) question on boiling water

I put a glass bottle in a big pot, bottleneck up, I fill both pot and bottle with very hot water. The bottle is submerged except a few cm of the bottleneck and filled to the brim so some water ...
11
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3answers
528 views

what is this force that is able to surpass an entire planet's force on it?

I have a wet teabag in an empty cup. If I will hold the teabag and touch the wall of cup with it, it will stick to the cup, like there would be glue or some magnetic field, but there's just water. ...
2
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1answer
128 views

Does increasing diameter of a water pipe increase speed or volume?

Let's say water is flowing from an arbitrary Source to some arbitrary Sink via a small pipe: I'm curious as to what actually ...
1
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1answer
58 views

Salt water evaporation

Pardon my no-knowledge of the topic but I am curious about following characteristics of sea water evaporation: is it more efficient to have thinner ponds to which water is re-added or deeper ponds? ...
5
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2answers
161 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.) ...
4
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0answers
51 views

What is the deepest cause of the such high specific heat capacity of water?

Yes, I know about the hydrogen bridges. But I think, it isn't the deepest cause. Anyway, they are only second-order bindings, although quite strong. I think, somehow should have the water a ...
6
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2answers
111 views

Flying eggshells

This question was asked on Judaism.StackExchange a few days ago, but I think it has a better chance of being answered here. Disregarding the grammatical discussion in the comments on that ...
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3answers
59 views

Why are some surfaces slippery?

Why are ice and oil slippery? In general, why do certain substances make a surface difficult to walk on?
2
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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?
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0answers
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Rapids in a River

Can I expect to have bigger or smaller rapids in a river that has a water level that is higher than average? I am not sure which way this would go. With the lower water, one is closer to the rocks, ...