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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1answer
516 views

Why does the water in the toilet move around so much on stormy days?

On calm days, the water in the toilet looks completely still. But when it's rainy and windy out, the water looks like it moves and pulsates. Why is this?
6
votes
1answer
375 views

What is highest water pressure at which electrolysis can be performed?

What is highest water pressure at which electrolysis can be performed to derive hydrogen and oxygen? Does the dielectric constant of water, which which lowers as pressure increases, have an effect on ...
5
votes
2answers
221 views

What reflective media do laser shows use?

I am having a hard time in finding out what exact light media laser shows use. I am trying to build a laser show myself. I know that the laser light is reflected off these particles in such a way that ...
7
votes
1answer
763 views

water flow in a sink

When one turns on the tap in the kitchen, a circle is observable in the water flowing in the sink. The circle is the boundary between laminar and turbulent flow of the water (maybe this is the wrong ...
1
vote
2answers
684 views

Tube under water and air pressure

If you take apart a syringe you are left with one piece that is a tube with a tiny hole in one end and the open end of a tube at the other. If you then submerge this underwater and cover the small ...
1
vote
1answer
266 views

Extracting water out of silica gel [closed]

From my preliminary research I've learned that desiccants are a good (best?) method to absorb water from air. Assuming I'm using silica gel (or kitchen salt, or rice) then what is the best way to ...
6
votes
1answer
261 views

How to simulate a crashing wave?

I'd like to create a very rough animation of a wave crashing on a beach. I'm guessing it would have to be a particle simulator, where you code in the forces between the particles and then integrate ...
0
votes
0answers
211 views

Is the Hanging Gardens of Babylon mystery still unresolved? [closed]

I'm wondering if the water lifting secret method of Hanging Gardens of Babylon still unresolved. I tried to find anything related to it at Google Patent but nothing was there related to it. Does ...
13
votes
5answers
5k views

Why do tsunami waves begin with the water flowing away from shore?

A sign of a tsunami is that the water rushes away from the shore, then comes back to higher levels. It seems that waves should be both + and - polarized and that some tsunamis should go in the ...
8
votes
4answers
1k views

Are water waves (i.e. on the surface of the ocean) longitudinal or transverse?

I'm convinced that water waves for example: are a combination of longitudinal and transverse. Any references or proofs of this or otherwise?
5
votes
4answers
284 views

When displacement isn't possible

Stop me if i'm wrong but displacement is, for example, when you enter a bathtub the water level rises around you. What happens when displacement isnt possible? I'll give an example. I have two ...
3
votes
4answers
323 views

Withstanding charlatans: How to protect friends from buying “water structuring facilities”?

In my country it is a big business now, to sell "water structuring facilities". Promoters telling that after passing through them the water obtaining fantastic abilities basing on the fact that "water ...
5
votes
3answers
4k views

Is it really possible for water to be held in a “cone shape” for a brief period of time?

I just saw this "trick" where a cup of water is turned over onto a table without spilling (using a piece of cardboard. After removing the cardboard from underneath the cup, the person then removes ...
2
votes
3answers
4k views

Explanation for different boiling points of water on different altitudes

I understand water boils at different temperatures depending on altitude. I am seeking to get an illustrative explanation for this, including a diagram if possible.
5
votes
1answer
169 views

Resonance modes of a cubic box of water which we shake

I don't know hydrodynamics, but I wonder how one would compute resonance modes of a cubic box of water which we shake. I believe the waves would directly depend on the height of water and the width ...
4
votes
1answer
1k views

Why is there more steam after a pot of water *stops* boiling?

I have a pot of vigorously boiling water on a gas stove. There's some steam, but not alot. When I turn off the gas, the boiling immediately subsides, and a huge waft of steam comes out. This is ...
5
votes
5answers
3k views

Eyes open under water

Yesterday I looked underwater with my eyes open (and no goggles) and I realized I can't see anything clearly. Everything looks very, very blurry. My guess is that the eye needs direct contact with air ...
0
votes
1answer
221 views

Why is sometime it raining heavily but in a short time but in other time not so heavy but long? [closed]

Don't they pour down just the same amount of water at the end of the day? I mean in the tropical countries.
2
votes
1answer
986 views

Do my noodles cook quicker when the water is boiling or when it is just about to boil?

I was just cooking some noodles and staring at the pot waiting for them to cook made me wonder... Will my food cook quicker when the water is boiling and bubbling, or when it is at a temperature where ...
12
votes
4answers
2k views

Why are snowflakes symmetrical?

The title says it all. Why are snowflakes symmetrical in shape and not a mush of ice? Is it a property of water freezing or what? Does anyone care to explain it to me? I'm intrigued by this and ...
6
votes
3answers
2k views

Why does frozen water burst a pipe?

When water freezes in a pipe it can crack the pipe open. I assume this takes quite a lot of energy as when I try to crack a pipe it can be hard work! I think water freezing is a result of energy ...
4
votes
1answer
749 views

How can I prevent drinking water from freezing in cold weather? [closed]

I'd like to keep a container of potable water in my car for when I get stuck, but in the winter it gets cold enough for bottled water to freeze. I can't put salt in it, because then it won't be ...
4
votes
2answers
430 views

Why does a slight drip of water protect pipes from freezing?

I've heard that turning on faucets to a slight drip will prevent pipes from freezing, but I've never understood why this is the case. Can anyone out there help me to understand? Thanks!
1
vote
2answers
3k views

How does watering your plants help protect against freezing?

I've always heard that watering plants if the temperature goes a few degrees below freezing will help prevent them from freezing, but I've never quite understood the physics behind it. Can you guys ...
4
votes
1answer
1k views

How cold does it need to be for spit to freeze before hitting the ground?

What is the dominant form of heat transfer between warm water and cold air? If a $100 mg$ drop of water falls through $-40 C$ air, how quickly could it freeze? Is it credible that in very cold ...
10
votes
4answers
5k views

Why does adding solutes to pure water lower the the specific heat?

We found that water with salt, sugar, or baking soda dissolved in it cools faster than pure water. Water has a very high specific heat; how do these solutes lower it? We heated a beaker (300ml) of ...
7
votes
3answers
2k views

Waves in water always circular

I have had a question since childhood. Why do we always get circular waves (ripples) in water even when we throw irregularly shaped object in it?
11
votes
3answers
919 views

A water drop in vacuum

Let's imagine the following situation: At an initial moment $t=0$, a large water drop with diameter for example $D=10\ \text{cm}$ is placed in deep space (Say an astronaut is experimenting). Let's ...
4
votes
1answer
229 views

How to estimate condensation from air?

How to estimate the amount of water condensing from air on a surface, given the air's temperature and relative humidity and how they change over time, the surface temperature, material's thermal ...
6
votes
3answers
2k views

Why does the water level equalize in a series of tubes?

Say I have a series of tubes (not the internet) looking like this, where w represents water: ...
6
votes
5answers
2k views

Why does water make a sound when it is disturbed?

When I disturb a body of water, what causes the familiar "water moving" sound?

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