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
216 views

How does ice become thinner inside a no-frost fridge?

How does ice become thinner in a no-frost fridge? I thought ice can't evaporate at all since, well, it's below freezing temperature and it's solid, too. In my other yes-frost fridge, the ice never ...
23
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9answers
24k views

How can water evaporate at room temperature? [duplicate]

Boiling point of water is 100 degree Celsius. The temperature at which water in liquid form is converted into gaseous form. Then how it possible for water to evaporate at room temperature?
25
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4answers
66k views

How does water evaporate if it doesn't boil?

When the sun is out after a rain, I can see what appears to be steam rising off a wooden bridge nearby. I'm pretty sure this is water turning into a gas. However, I thought water had to reach 100 ...
1
vote
1answer
144 views

Different solutions for floating a DIY torii gate deeper than it's original floating level [closed]

I'm facing a dead end with my physics experience on a new build I am working on. Any help would be appreciated. Basic problem: I am trying to build a floating wooden Torii gate to be placed on water ...
4
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2answers
809 views

Why does my kettle only make a noise when it is turned on

Almost as soon as I turn my kettle on it starts to make the familiar kettle noise, yet very shortly after turning off the power the boiling noise stops and the kettle is totally silent. The ...
4
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2answers
131 views

The velocity of a cloud?

I noticed an unusually fast moving cloud this morning. My questions: What is the average velocity of a cloud on Earth? What is the greatest ever recorded cloud velocity? What factors affect the ...
12
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4answers
3k views

Thermodynamics of supercooled water

Now that it's been freezing outside for the last few days, I experimented a bit with supercooling. I've left a bottle of clean water outside for a few hours, and behold, when I shook the bottle, the ...
43
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4answers
5k views

Why is water clear?

Water appears transparent to visible light, yet most other objects are opaque. Why is that? Is there an explanation why water appears transparent? Is water transparent at all wavelengths, or are ...
5
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1answer
133 views

Is nuclear fusion via underwater vacuum possible?

An under water explosion creates a bubbly which quickly collapses on itself. The action takes less that 1/100 of a second for bubbles less than a foot across. This creates a point of extremely ...
4
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1answer
178 views

Water falling, why does it spin?

I have noticed that water, when falling will rotate. Looking closely at a thin stream from a faucet and placing a flat object mid stream you will see the water is rotating. The further down the stream ...
3
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1answer
146 views

Why is the water on one side of a bridge choppy?

My daily commute take me across the Evergreen Point Floating Bridge on Lake Washington. I have noticed on several occasions that the water on the southern side of the bridge will be quite choppy ...
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0answers
55 views

Why color of dress changes when water falls? [duplicate]

When you drop water to dress actually the color changes, that is the color of dress becomes dark, but when you add water to color, for example water color or poster color it becomes light. Why is it ...
9
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0answers
240 views

Ice cube left in water at 0 °C for a thousand years

Let's say we take an ideal calorimeter with a liter of water at +5 °C and throw a 5×5×5 cm cube of ice having temperature of –70 °C. I choose these initial parameters so that the stationary ...
2
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1answer
159 views

Continuity and Blood Flow

Consider a tube with two different diameters (one section wider than the other). Because what comes in must go out (conservation of mass), the flow rate in the wider section must be the same as the ...
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3answers
615 views

Using water to amplify sound

It seems that water generally dampens sound waves. Is there any way one could attach a speaker to a body of water in such a way that the water would actually amplify some frequencies (for nearby ...
1
vote
1answer
199 views

Why does a bucket of Water weigh more than a bucket of Air?

Given the numerous chemical compounds found in dry air [compressed into a liquid] of a given volume [lets say $22.4$ L for simplicities sake] whose atomic weights far surpass that of water alone ...
3
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3answers
557 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 ...
0
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3answers
118 views

Raindrops on a fence. Why a regular pattern?

I observed a fence composed of plastic-coated metal wires running vertically and horizontally at intervals of around 3 cm. After it had rained, drops of water remained on the horizontal wires. I was ...
21
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4answers
582 views

Why is lightning more rare during snow storms than rain storms?

Lightning and thunder during a snow storm is uncommon. As far as I know, more uncommon than during a typical rain storm. Why is this? I speculate it might be one, or both, of the following two ...
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2answers
127 views

Should water cool faster if is inserted metal canister with ice inside either mix only with ice?

Let's say that we have two canister first bigger (metal canister 2l) with 1l of water at 100C, and second smaller (metal canister 1l) with 1l of ice. And we want to cool down boiled water to 50C. So ...
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2answers
829 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 ...
-1
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2answers
249 views

If a planet were cut in half but stayed hemispherical, how hot would the ocean on the flat side be? [closed]

Some time ago I asked a question about gravity on a hemispherical planet. What would gravity be like on a hemispherical planet? Would the water all boil away at first, quickly cooling the core of ...
3
votes
1answer
50 views

What is the equivalent of a eutectic point for a (two-liquid)+solids system?

I deal with complex phase equilibria involving solid and liquid phases at high temperature. Below is a simplified temperature-XH2O diagram for a multicomponent system at constant pressure. (Note: ...
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3answers
431 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
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3answers
128 views

cooling glass of milk glass and a jar of water

When im given a steel glass of boiling milk which I cannot even touch, I used to put that glass in a jar surrounded with room-temp water and give it 10 mins. At the end, I used to find the steel glass ...
5
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1answer
78 views

What are circles on broth (eating soup) surface?

Think about broth in the soup, usually it has circles on its surface. What are their properties? Why there are many of them (not a few big blobs)? Are they depended on liquid's temperature? What needs ...
4
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2answers
9k views

Flow of liquid among branches

If water is flowing through big pipe is branched into 4 branches of small pipe. Lets say the flow is around 4 m/sec. I have the following questions: What will be the flow rate in each of the ...
4
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2answers
73 views

Why water vapour condense easier in contact with a solid?

Reading about cloud formation, I learned that to a droplet to form, the water vapour needs a Cloud Condensation Nuclei, which is an aerosol with a size in the order of 0.0001mm. And if no CCN is found ...
3
votes
2answers
2k views

Why doesn't the water spill out?

In this experiment, a number of coins are put into a cup full of water, without spilling it. http://www.youtube.com/watch?v=N2mKpZHnEzw Firstly, let me clarify one thing. If you fill up a cup ...
8
votes
2answers
485 views

How to model the form of a surface water wave?

Normal surface water waves, as generated by wind, do not have sine form but wave peak is higher and shorter than wave trough with different wave steepness. What parameters characterize such a surface ...
3
votes
1answer
2k views

Where are the ice rings in X-ray crystallography located?

I threw this image of one of my protein crystal's diffraction pattern (not the greatest) on a poster, and was wondering where (what reciprocal dimension) the ice rings are located as it might be a ...
44
votes
4answers
4k views

Being in a solid state, why is ice slippery? [duplicate]

Saying that ice is slippery is like saying that water is wet -- it's something we've known for as long as we can be said to have known anything. Presumably, humans as a species knew ice was slippery ...
2
votes
2answers
480 views

Would sea water moderate a nuclear submarine meltdown?

My son asked me: If nuclear submarines get sunk or blown up, what is to stop them going into nuclear meltdown? I thought about it and came to the conclusion that because they're in the sea the ...
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vote
2answers
158 views

What is a good model for computing water dropping on a surface?

Before introducing my question I would like to outline the fact that I'm a coder, so I can be wrong when using some kind of terminology. What is a good model for computing the flow, the shape and all ...
4
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2answers
149 views

Dynamics of Honey in hot water: Honey accelerates like it is falling through air?

Here is a Video showing the honey accelerating in the hot water. As you can see, there are also dynamics. Since the water started stationary, I guess the dynamics arise because of convection flow. ...
17
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6answers
6k views

Why does ice form on bridges even if the temperature is above freezing?

So with this "arctic blast" continuing, I've noticed that for my area, the temperature drops below freezing just long enough to cause freezing rain, but then the sun comes out and the temperature ...
-1
votes
1answer
132 views

Slope of a channel

I have a trapezoidal channel like this: The question is to get the slope of the channel such that we have a Chézy coefficient of 64 $m^{1/2}/s$. Given: $B= 76\: \mathrm{m}$, $y = 10\: ...
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3answers
1k views

Why are oxygen and hydrogen compressible, but water is barely compressible

What makes the two gases compressible, but does not apply to a liquid like water?
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vote
0answers
109 views

Gerstner Wave Formula to Vertex information $(x,y,z)$

I have created a program, that draws a plane mesh, and allows to me edit or animate all the separate vertices along it. The idea behind it, is for me to be able to create a gridMesh based wave ...
3
votes
1answer
105 views

Can ice thickness be different on two nearby lakes?

In winter, is it possible for two distinct bodies of water, which are a few kilometers apart (so they are exposed to roughly same temperature), to have different thickness of ice? Does the area of the ...
0
votes
1answer
1k views

Which one conducts heat better: water, or air?

If we were to assume room temperature of 20C, which of the fluids conducts heat better, and why?
2
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2answers
535 views

Measuring background radiation

We tried to measure background radiation using a geiger counter for a experiment at school. The meter showed $0.12$-$0.21$ microSv/h during the day averaging at about $0.14$ mcSv/h. As we tried to ...
2
votes
1answer
107 views

Non-determinitric flow of water stream on vertical porcelain surface

I noticed several times while washing my hands that accumulated water when starts streaming vertically does not flow vertically in straight line on vertical porcelain surface under the force of ...
0
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2answers
400 views

Is it possible to project an image onto water? [closed]

Is there a way to create an image/projection in the water? Or form the water to project an image, little dot/pixel? Use some type of frequency to modulate the little dot in the fluid?
-1
votes
2answers
280 views

How long will it take to fill a bath tub with oil compared to water?

As everyone knows, the oil is more viscous than water. But, I've been wondering how long it will take to fill a bath tub compared to water. It is quite obvious that oil will take longer. But, how much ...
0
votes
0answers
47 views

Optimal temperature for Mpemba Effect

Is there an pptimal temperature for the Mpemba Effect? Is there an optimal initial water temperature for speedy freezing? If so, what is it? If a specific example is needed: There is a 100 milliliter ...
4
votes
4answers
385 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 ...
2
votes
1answer
92 views

Why water from upper level not goes into lower level in this drainage system

In the following typical water drainage system, I'd like to know why waste water from upper floor (let say, from 2nd floor's toilet) does not come to the lower floor's equipment via the common pipes ...
1
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0answers
172 views

How much heat needed to heat 400g of ice at 0°C to 20°C in a 200g aluminium pot? [closed]

An aluminium pot has a mass of 200g and contains 400g of ice at 0°C. How much heat would be needed to melt that ice and then raise the temperature of the resulting water to 20°C. The specific heat ...
13
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3answers
2k views

How to freeze the Niagara waterfalls?

Here is a picture of the usual vigorous Niagara Falls (in the winter). Here is the picture of Niagara Falls frozen in 1933 (in the very cold winter). Here is the picture of Niagara Falls frozen in ...