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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4
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2answers
339 views

Why do some things crystallize? (And others don't, for that matter.)

Ice, for example, will form a crystal when frozen under certain circumstances. Why is this the case for ice? While on the subject of water crystallization, why do snowflakes usually form in base 6 ...
3
votes
1answer
121 views

Mysteries of the water meter

Recently, I got an exceptionally high bill for water consumption. I went to check my water meter, and saw that it rotates in a pace of about 200 cc per minute, even though all the faucets in my home ...
1
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0answers
213 views

Rate of evaporation of water

In our everyday life, does the temperature or humidity have a greater effect on how fast things dry? Are there any theories/models that explain this quantitatively?
2
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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 ...
19
votes
4answers
4k views

Why does boiling water in the microwave make a cup of tea go weird?

When I boil water in the kettle, it makes a nice cup of tea. Sometimes I need to use a microwave because a kettle isn't available. I boil the water in the mug and it looks pretty normal, but when I ...
0
votes
1answer
404 views

Is there a way to let water pour out of bottle without letting air inside? [closed]

Is there a way to let water pour out of bottle without letting air inside? i understand that air needs to enter the bottle to ensure water flow, but i do not want to the water to be exposed to air. ...
1
vote
1answer
125 views

Does the termination point(level) influence water flow from a pipe

I get water to my home from a nearby Tank A at a certain height above ground level. I have a 1" pipe through which I get this water to my home.. I leave this water into my well by connecting a 1" tube ...
3
votes
2answers
425 views

Would a small puddle of water evaporate faster if you spread a dry towel over it?

Let's say you spill 10ml of water on the kitchen counter. It forms a small puddle that would evaporate after a while (assuming room temperature and sane humidity). Would spreading a large, dry towel ...
0
votes
1answer
252 views

How to heat swimming pool with physics principles [closed]

I'd like to apply physics principles to a home-experiment relating to my swimming pool. The water should flow inner to 100 meters of black pipe and so it should become warm. Then it should return in ...
1
vote
2answers
112 views

Possibility of determining the mass of the water without a scale?

Possibility of determining the mass of the water by knowing water volume, water temperature and atmospheric pressure. I want to know if I can determine the mass of $V=0.01\,m^3$ of water in ...
5
votes
1answer
687 views

Does something like Pascal's Law apply in a Swimming Pool? If not, how does pressure spread?

I've been trying to wrap my head what happens when a force is exerted on the surface of a swimming pool / pond, or underneath it. Examples include a small boy cannon-balling into the deep end, or a ...
5
votes
1answer
545 views

Does a domestic microwave work by emitting an electromagnetic wave at the same frequency as a OH bond in water?

I was told once that microwaves work by exciting water molecules in food. Also that this worked because the frequency in the microwave was the same as that in the bond between Oxygen and Hydrogen in ...
0
votes
0answers
59 views

Is it possible for a planet to be made entirely of water (even it's core)? [duplicate]

I was thinking about this today... Is it possible for a planet to be made almost entirely of water (H20)? I'm sure that other elements would be in the mix, but I mean almost entirely made of water. ...
3
votes
3answers
341 views

Would a sea level rise (on the other side of the Earth) if you would dip your finger into the ocean?

(I'm not a physicist & I hope this question isn't too basic/lame) The question says it all & assuming: No atmosphere No Earth rotation Not a single object in the ocean(s) Ignore all other ...
25
votes
4answers
4k views

Why does wet skin sunburn faster?

There is a popular belief that wet skin burns or tans faster. However, I've never heard a believable explanation of why this happens. The best explanation I've heard is that the water droplets on the ...
2
votes
1answer
183 views

Is a tankless water heater more or less efficient than an electric stove at heating water?

Consider the following scenario that I actually encounter frequently: I just finished washing a pot in the sink, and now I want to boil some water for cooking noodles. If I fill the pot with hot ...
4
votes
2answers
331 views

Why is steam used to spin turbines?

The ideal gas law tells us that the relationship between Pressure (P), Volume (V), Temprature (T), and quantity/amount (n) is $$ PV = nRT $$ where R is the gas constant. Say your an engineer who ...
6
votes
0answers
77 views

Can a submerged place in the sea have huge air pockets? [duplicate]

I know that air can be under water if there is something to contain it that prevents its escape. But can a place such as buildings or ancient ruins submerged totally under water hold air pockets as ...
10
votes
2answers
2k views

Is there a way to fill Tank 2 from Tank 1 through Gravity alone?

I am a newbie in water system design but I am currently faced with the exact situation below on my land, and I need to know whether gravity alone is sufficient in order to fill Tank 2 from Tank 1, as ...
3
votes
1answer
2k views

Time required for water to freeze

recently I was wondering if there is any specific formula in order to calculate how long it takes for certain liquids to freeze (especially water). I know this depends on: the volume of the liquid, ...
1
vote
1answer
183 views

1/2 freeze a water bottle

Is it possible to quick freeze half of an unopened bottle of water or soda by putting half of the bottle in a subfreezing solution liquid nitrogen or other solution without freezing the whole bottle?
131
votes
3answers
39k views

Surviving under water in air bubble

An incredible news story today is about a man who survived for two days at the bottom of the sea (~30 m deep) in a capsized boat, in an air bubble that formed in a corner of the boat. He was ...
2
votes
1answer
243 views

Reflections in a glass of water

I've noticed that if you take a full glass of water and look from above, through the water, you can't see through the glass sides - instead, you see a reflection. I tried with a laser pointer and the ...
4
votes
4answers
266 views

Dissolving oxygen into water

I was wondering how one would actually calculate how much oxygen would dissolve into water given the necessary initial conditions, and what those initial conditions would need to be. I assume they ...
1
vote
2answers
536 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 ...
2
votes
1answer
93 views

How to homegrow large, momocrystalline water ice crystals

This is a follow up to this question:Can one get clear ice crystals from a dirty suspension?. How could one grow a large - meaning visible with the naked eye - water ice crstal with common household ...
3
votes
3answers
1k views

Why is it faster (as in proportion to volume) to boil 4 cups of water than to boil 2 cups?

I did an experiment where I boiled two cups (500ml) of water in a kettle, and it took 1:30 minutes to reach around 98 C, average. However, when I boiled 4 cups of water, (1L) it only took me 2:30 ...
6
votes
5answers
721 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 ...
0
votes
1answer
206 views

Does brown but transparent swimming pool water heat significantly faster than western style highly chlorinated pools?

Eastern European swimming pools are often brown tinted water. i was told it was the color of the chemical to keep the pools clean, but who knows. These pools did not smell unsanitary and may have even ...
2
votes
0answers
86 views

Can one get clear ice crystals from a dirty suspension?

Euteictic freeze crystallization is a method where an electrolytic solution is cooled and separated into a stream of (relativly) clean, pure ice and a salty brine. I know anectdotally of wine ...
0
votes
1answer
131 views

Absorption of Water

I was just watching the videos Chris Hadfield put on youtube from space, and was wondering why water doesn't get absorbed as well onto his toothbrush in space? And what characteristic of ...
4
votes
1answer
250 views

Finding Surface Tension of water at certain Temperature and Pressure

So the question is: Using the Young-Laplace Equation (if applicable), find the surface tension (dynes/cm) for water at 20 degrees Celsius with 2.5 psi. Round to the nearest tenth. ...
0
votes
1answer
1k views

Calculating the coefficient of thermal expansion in liquid

I am trying to write a matlab function that calculates the coefficient of thermal expansion of water from a given temperature. From what I understand the thermal expansion coefficient is calculated as ...
0
votes
1answer
235 views

Water evaporation

It is known that molecules at the surface are strongly attached to each other (more attraction less repulsion) than those within the bulk attraction and repulsion are balanced). This is the molecular ...
-2
votes
1answer
373 views

Time constant of ice melt

I'm familiar with problems of "how much ice can you melt given some amount of energy", but I'm writing to get some clarification on the time constant of this event. This question might be somewhat ...
7
votes
5answers
849 views

Why the water remains on the surface of the Earth?

What makes the water stay on the surface? Why the earth does not absorb the water in it?
0
votes
1answer
242 views

Does electrically heated water have an adverse effect on hair?

I know I should have asked this question on a different site. but this was the most suitable site available right now for my question. Perhaps after this proposed site goes on Beta, we can move it ...
3
votes
1answer
199 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 ...
3
votes
1answer
219 views

How to create visible reflections in shallow water?

Assumption: The only lights I have are candle, table lamp, and sunlight. What would I need to create visible reflection of an object in the shallow water contained in a 5 liter bucket? Is it even ...
5
votes
2answers
831 views

What is the largest sphere of liquid water that could exist in space held together under it's own gravity? [duplicate]

What is the largest theoretical sphere of liquid water that could exist in space held together under it's own gravity? I've always wondered if a planet the size of earth could exist as a single volume ...
3
votes
1answer
219 views

Make water droplets charged?

Normally water molecules are electrically neutral. But I have seen somewhere ideas about electric energy generators mentioning that water droplets might be used in some applications as they are ...
7
votes
2answers
489 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
410 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
21k 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
706 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 ...
10
votes
1answer
249 views

Phase transition water

The water-gas phase transition is said to be similar to the ferromagnetic-paramagnetic phase transition (same set of critical exponents = same universality class). In the former case the order ...
1
vote
1answer
486 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 ...
8
votes
1answer
491 views

What determines bubble locations in boiling water?

Something a little different to our usual fare. I was boiling a pan of water for cookery the other day, and got to wondering what caused the location of the bubble streams from the bottom of the pan. ...
-2
votes
3answers
235 views

Water excitation with sine waves

I saw that video when they connected a water hose to a speaker emitting 24 hz sine wave, and its illusion on the shape of the follow going out of the hose (because the video capture rate is fixed at ...
1
vote
2answers
599 views

How long will a water drop exist until it evaporates based on ambient conditions? [closed]

How long will a water drop exist until it evaporates based on ambient conditions? I am looking for a simple equation or table that would tell me how long a water drop may exist until it evaporates ...