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

learn more… | top users | synonyms

0
votes
0answers
12 views

hydrostatic pressure on a plane surface

I've been trying to calculate the amount of pressure on a wall of a rectangular structure, that is under sea watter. For example a dam. I can't come to see any example to be able to locate the ...
0
votes
0answers
13 views

watter remaining liquid in low temperatures

On several occasions I have witnessed the following phenomenon and would like to understand the physics behind it: Water is placed in a very cold static location, in a cup or plastic bottle in a car ...
0
votes
0answers
26 views

An interesting question on the mass of a droplet of liquid experiencing the Leidenfrost Effect

Background and Inspiration: I have seen numerous demonstrations of the leidenfrost effect, both on the internet and in my mother's kitchen. But I started wondering about a general case after having a ...
0
votes
0answers
63 views

In every glass of water there are water molecules that came through Hitler's urinary bladder? [on hold]

I was told that in every glass of water there are water molecules that came through Hitler's urinary bladder. How much it is true probabilistically?
6
votes
2answers
586 views

Is it possible to disprove water memory with an entropy argument?

Water memory was a controversial experiment claiming to provide an explanation supporting homeopathy. The results were largely dismissed as being tainted by experimental error. One possible mechanism ...
2
votes
1answer
66 views

How to heat water at very high temepratures?

I am working on a project and recently came through a situation where I'll be working with water evaporation. On searching the internet I found that water heated at 350Celsius would generate almost ...
4
votes
1answer
126 views

Can ice freeze? [closed]

We know that ice is already the frozen (solid) form of water. The question is more like: Can this frozen form freeze further? Or can it become more solid? (for example, by exposing to colder ...
1
vote
0answers
22 views

Will a longitudinal wave propagate “forever” in a tube?

I understand that the wave will lose energy due to "friction" between the, lets say, water molecules, but in my mind at least the biggest loss of energy in a wave is normally the dispersion of it. ...
1
vote
3answers
83 views

Why does a metal boat float?

I was in class learning about density and stuff. Our teacher told us that things that are denser than water sink in water, and less dense things float. Then, our teacher asked us why metal boats ...
2
votes
1answer
52 views

Why does ice melts faster near the surface of water?

I had a few frozen bottles and while they were melting I saw this: in all of the bootles, the ice seems to get thiner near the surface. I have searched a bit and I've found this video that shows ...
4
votes
0answers
108 views

Calculation of water bulk modulus using equation of state

I simply want to calculate the bulk modulus of water at 50C and increasing pressures. I think I am correctly calculating the new specific volume from the original conditions at (25C and 1atm) to 50C ...
4
votes
1answer
45 views

Is the IoR of water exactly $4/3$?

The index of refraction of water is commonly cited as $n \approx 1.33$, to varying numbers of decimal places. I've never seen a decimal expansion for this value with any digit other than $3$ past the ...
1
vote
1answer
49 views

Equilibrium between two water tanks

I've been reading about hydrostatic theory, however I couldn't find a similar case/exercise about my basic problem. I have two water tanks (same size) filled with different water heights, and ...
5
votes
0answers
87 views

What would happen to a submarine coated in water repellent

I saw the article about laser-etched hydrophobic metal, and it got me thinking, how would a submarine function differently if coated as such? Would it move faster, sink completely, be unable to move ...
1
vote
1answer
36 views

Why does the surface structure of a metal make it hydrophobic?

I was just reading this article from phys.org describing water-repellant surfaces. However the article doesn't go into enough details of explaining why a particular structure repels the water. Can ...
2
votes
1answer
54 views

Can an electric field align water molecules?

Water is a polar molecule, which means it has an uneven charge distribution. How much of an electric field strength would it take to align all, or most, of the molecules at room temperature?
4
votes
3answers
87 views

Can liquid contain information?

Is there any principle in physics that would allow liquid to contain some kind of information - could we, for example, in theory, use a glass of water to save information? For example digital photo ...
1
vote
1answer
138 views

Can a liquid boil in a closed container?

The title says it all. When one fills a container (with water for example) and closes it so no air can escape from it, then heats the container continuously, can the liquid boil or completely ...
1
vote
1answer
55 views

Compute pipe restriction from water flow and static pressure

How can I determine if residential water pipes have a restriction given, for example, flow rate and static pressure? Details: (1) You hook up a static pressure gage to a faucet which is in the ...
12
votes
2answers
131 views

Why do crystals grow in preferred directions?

I want to know why snowflakes (and other crystals) grow symmetrically and I find the leading answer to the established question to be entirely unsatisfactory. When water freezes, you get ice. ...
1
vote
0answers
33 views

I need to remove water from a system [closed]

I work in an industry and I need to remove water from a system. The scenario: There is a washer and a blower on a conveyor belt. The item being washed is plastic (not sure what type) and can't be ...
0
votes
0answers
31 views

How can we describe or model the spread of ice during the freezing of the surface of a still lake?

Premise: I live in a place where it is unquestionably wintertime in every aspect of the phrase. I was driving down the street and I drove by a lake. There was a recent and sudden temperature drop ...
0
votes
0answers
17 views

Heating water with low and high gas heat

Similar type question is asked before but i'm looking for other aspect of it. I observed that if water is heated with low gas heat, it takes long time but it retains it high temperature for long time ...
3
votes
2answers
563 views

What air pressure is needed on mars, to have fluid water?

The atmospheric pressure on the Martian surface averages 600 pascals (0.087 psi), about 0.6% of Earth's mean sea level pressure. There is a lot of frozen ice on mars, but it can't melt, because of ...
0
votes
0answers
33 views

How much does grabbing a piece of a plane free falling change your survivial?

Just for context let's saying you are falling from a plane in free fall position at 56m/s(200 km/h or 120 mph) and you grab onto a wing which slows you down to 25m/s. You weigh 70kg. so ...
2
votes
2answers
144 views

Where would a perfect sphere break under pressure?

My roommate who studies physics once showed me the leftovers of an interesting experiment: They filled up those metal balls with water and then froze it. The water expanded and with all of its ...
2
votes
1answer
30 views

Would it actually be possible to preserve a snow flake?

In episode one of season 3 of The Big Bang Theory Leonard offers Penny as a gift a snow flake he says he preserved in some kind of resin, having it brought from the North Pole. Is this purely ...
21
votes
2answers
1k views

When a drop of water falls into water, where do the splashes come from?

When a drop of water falls into a reservoir of water from a high enough altitude, water droplets will splash (image credit): My question: Does the water in those droplets come from the original ...
1
vote
0answers
28 views

Bond Angle in a water molecule

I recently started up reaching up on the Feynman lectures on Physics and in Vol I,Chap 1-2,Feynman states that the bond angle between the hydrogen and oxygen atom is 105° 3′. I know that the bond ...
3
votes
3answers
78 views

Why do square shaped cups spill easier than round cups?

I've noticed that when I use a cup that is square shaped with convex sides, it spills more easily than a circular cup. Why does this happen? What is the most spill-prone cup shape? What is the most ...
4
votes
3answers
146 views

Why does a pitcher with lemon juice have foam, while one with pure water does not?

Whenever I pour water into lemon juice (pouring directly from the tap into the pitcher, not quietly along its edge) I get a foam on top: The same pitcher with water (same water tap, pitcher, time ...
3
votes
2answers
50 views

Water level of ice in cup [duplicate]

Since ice is less dense than water, it floats on it, we all know this. Now suppose, if ice is floating in a glass cup, when the ice melts there should be some change at water level in the glass cup. ...
6
votes
3answers
185 views

Why is concrete dry around cracks?

On a warm and partly cloudy day this summer, I was sitting in my office and suddenly heard rain on the roof. I went outside to shut my car windows. By the time I did that and was walking back into ...
1
vote
0answers
72 views

How can I bring water to 90 degrees C? [closed]

For my coffee I need the water to be 90 degrees Celsuis. Boiling water, however, is 100 degrees. How can I make it 90 degrees? Do I just measure the temperature of the water from my tap, and if it's ...
1
vote
1answer
34 views

How do you work out the energy requirement for a submerged pump?

I was wondering if you were to place a pump in a submerged container and then were to open a hatch allowing water to flood the previously vacant cavity how much energy would be required to discharge ...
1
vote
0answers
18 views

Will Ice Cubes Form Quicker when Made from Hot Water or Cold Water? [duplicate]

When you put water in the freezer you can make Ice Cubes. But does the time taken for these Ice Cubes to form decrease or increase when the water which is used is hotter or colder?
1
vote
2answers
86 views

Why does room temperature water and metal feel almost as cool as each other?

From what I've read about heat, temperature and conductivity, I understand that the reason water at room temperature feels colder than most other things at the same temperature (like wood, air, ...
0
votes
2answers
52 views

Why are ripples formed in water round? [duplicate]

Despite whatever be the shape of object that you drop in water, it be 1D, 2D, 3D, they all produce ripples in a circular pattern, is this pattern followed under water as well (in terms of density ...
0
votes
1answer
62 views

What Is the Physics principle behind dropping a stone into a cup of water?

I have been doing an experiment about relationship between drop height of a stone and the loss of water in the cup it lands in. I found that after dropping the same stone into a cup with the same ...
1
vote
2answers
60 views

Why Does Air Hold More Water When the Air is Warmer?

I know that when the temperature of the air rises, the maximum amount of Water it can hold before the water condenses to water droplets increases. But why is this - has it got something to do with ...
6
votes
0answers
57 views

Why is the splash of water always vertical, no matter in which angle the gunfire hits the surface

When gunfire hits the surface of a pond, the water seems to always splash directly upwards, in 90° to the surface of the water, no matter at which angle the gun is fired. The angle is usually very ...
5
votes
1answer
59 views

How does the movement of molecules change at the edge of a liquid?

I am thinking about how the velocity of molecules measured from a small region of space might change as the region of inquiry moves closer to the edge of a container. Ultimately I am thinking about MR ...
5
votes
1answer
66 views

Superhydrophobic coating and water friction

If you were to apply super-hydrophobic coating to the hull of ships or even submarines, would you get more or less water friction? If the coating completely repels the water you could argue there ...
3
votes
1answer
34 views

Why does the light reflecting off of ocean water sometimes appear 'smoother'?

Looking out the window at some water in the Harbour - I noticed that some parts of the water appear 'smoother' than others. My question is: Why does the light reflecting off of ocean water ...
2
votes
2answers
87 views

What would a graph of temperature increase of a cup of water in a microwave look like?

My lunch had been in the microwave for a minute or so, and I was wondering if I took it out 10 seconds early, would the amount of temperature it increased in that 10 seconds be more significant, less ...
0
votes
4answers
57 views

Is it true that water go down the drain counterclockwise in the northern hemisphere and clockwise in the southern [duplicate]

Many websites say that water drain in different directions in Northern, Southern hemispheres. Some people say that Coriolis effect causes it. Some people say that it's not true.
2
votes
1answer
49 views

Water behaviour under theoretical near-infinite pressure conditions

I've asked a similar question here but the answer given shows the behaviour of water under general conditions. I'd like to know what the behaviour of water is like as pressures increase towards ...
1
vote
1answer
20 views

What concepts/rules apply for multi-stage pumping of water

For single stage (ie one pump) water transfers calculations for pressure loss are commonly done by adding the elevation difference of the start and end of the pipe line to the friction losses that ...
1
vote
2answers
26 views

why only surface of water get frozen in polar countries?

why only surface of water get frozen in polar countries? but if i kept glass full of water in fridge then not only surface, whole water turns frozen ,why?
0
votes
2answers
89 views

Why does freshwater attenuate signals less than seawater?

One of the most interesting problem in underwater communication is how deep the device (i.e. submarine) could go to still be able to communicate with on-shore data centers. The attenuation in a ...