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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3
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44 views

Detect ions in water using impedance spectroscopy

I would like to check the presence of Na, Ca or other ions dissolved in water using impedance spectroscopy. I was thinking that because the ions have different masses they will have different ...
0
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0answers
19 views

How much power is being actually delivered by an electric heater to a cooking pan?

I've been doing experiments on an electric heater heating a cooking pan filled with 2 litres of water, from 20°C to 70°C; now I'm trying to draw a theoretical heat transfer model thath should match ...
1
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1answer
54 views

How does water height in a vacuum chamber effect pressure

I am testing for package leaks in non-porous packages. Quick details are: 1) Package is sealed at atmospheric pressure. There is some headspace inside the package which is just air. 2) A small hole is ...
0
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1answer
26 views

Why do water droplets not form on large openings such as pipes?

When you have an object with a small opening, such as a pipette, water droplets form and hang easily. However, when you have a larger opening such as a pipe, the same water droplets do not form. Is ...
-4
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1answer
104 views

Why does microwaved water kill plants? [closed]

I've read tons of articles about microwaved water klling plants and the most of them said it was a myth. So I decided to do this experiment myself on cress plants. I repeated the experiment three ...
0
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0answers
32 views

Is an “underwater” submarine affected by a nuclear bomb exploding above the water? [duplicate]

I've just read Would being underwater help survive a nuclear bomb?. Submarines are way more armored and far from the surface than a human body (https://en.wikipedia.org/wiki/Submarine_depth_ratings), ...
1
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1answer
74 views

Is water boiling an excited state?

I was wondering and arguing (pro) with a friend that the process of water boiling is an excitation. I based my opinion on the theory that excitation is an increase in the energy level of an atom. I ...
0
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1answer
40 views

Why doesn't the fridge condense water like an air conditioner? [closed]

Simple question, why doesn't the fridge condense water like an air conditioner? I know that my ac condenses water (even in cool or heat) and don't know why the fridge doesn't. Aren't they both ...
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2answers
38 views

How many water wheel can fit on a river until another one produces zero energy?

Mostly what I'm after are the factors I need to know to do the problem. Imagine we're in the days of Leonardo Da Vinci. And pizza is everyone's favorite food. And there's a river that goes on ...
1
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1answer
27 views

Force on sides of a pool [closed]

I am going to create a large pool of water for a stage production. The volume of water will be 6m x 5.2m x .15m deep. I want to check how much pressure or force will be exerted on the surrounding ...
0
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0answers
54 views

Solving propulsion force of water rocket

As a note, I am not a physics student, although I am familiar with many physics concepts and calculations. I am trying to calculate the force of the thrust of a water rocket. I started with the ...
1
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1answer
47 views

Best frequency for Underwater Transmission

What is the best frequency of transmission of under the water for communication with good data rate? I have read that the threshold of hearing underwater is around 170 to 180 db. Can this be useful in ...
0
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1answer
16 views

By which factors are tides and waves affected?

To my understanding, the tides and waves on Earth's oceans are caused by various factors such as the moon's gravity, the water cycle (rains, storms, evaporation), Earth's rotation, etc. Although the ...
0
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1answer
18 views

Simulating open water acoustics in a tube

For the purpose of testing an underwater acoustic transmission it is possible to use a tube filled with water with a transducer at one end and a hydrophone at the other. The problem is that sound will ...
1
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1answer
37 views

How do buoyancy control devices (BCD) work?

I get that having more air decreases density and increases buoyancy. However, we can take the diver-BCD-oxygen-tank to be a single system. How can the pumping of air from the tank into a vest around ...
0
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2answers
121 views

volume of the air bubble in the water

How does the depth affect the volume (the radius) of an air bubble in the water, if the temperature and density of the water are constant. Is there any relation combining this? Can I say that ...
3
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1answer
51 views

How quickly does the temperature rise in a water container submerged in a hot water bath?

Let's assume I have a small bottle (neglecting any insulation from the walls of the bottle) containing e.g. 150ml water at 4°C and place it in a larger pot with sufficient water at 80°C so that the ...
1
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4answers
118 views

The impatient hot tub owner [closed]

An impatient man owns a 300 gallon hot tub. He comes home from a hard day of work and sees that his hot tub is currently simmering at 90F. For maximum relaxation, he wants it at 104F. However, the hot ...
1
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2answers
106 views

Does shaking a kettle whilst boiling increase the temperature faster than a statically-placed jug?

Water molecules move faster at higher temperatures. Does shaking a boiling kettle whilst it is in the process of boiling water increase the rate of rising temperature ? Is it worthwhile to do so ...
0
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0answers
15 views

Is there a relationship between maximum flow rate of a fluid through perforations in a cavity and the flow rate of the fluid in the cavity itself?

I have a scenario where water is flowing horizontally through a (rectangular) cavity. The underside of the cavity has a set of perforations that look something like: and I need to determine the ...
0
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0answers
47 views

Can 1km diameter ball of water preserve it's integrity before hitting the ground falling from 10km altitude?

I still argue with my friend over some big ball of water (1km in diameter) that is being instantly created 10km over the surface of the earth in perfect sphere form. I stated, that as it hit the Earth ...
3
votes
3answers
325 views

Effect of initial suction power on siphon performance

Background I have a flooded crawl space and I'm using a long hose to siphon the water out. I do this as follows: One side of the hose is in the crawl space, and the other side down a hill in the ...
3
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1answer
73 views

A model for constant temperature of water in a container

I put some water in a container with initial temperature $T_0$ in a room, and the room's initial temperature is $T_a$. Now the container is filled to the maximum, so any more water coming in will ...
1
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1answer
54 views

How does water at different temperatures behave when they are mixed? [closed]

If I were to inject a constant flow of water at T1 into a reservoir of water at T2, how does that effect the temperature of the mixture at different points in the reservoir? In other words, what ...
2
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2answers
242 views

Are raindrops actually “shaped like tears” when they fall?

Raindrops are always pictured like this, people imagine they have this shape when they fall, but is this true? Doesn't this shape create too much drag? What shape do they really have? It would also be ...
2
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0answers
33 views

Does a rapid temperature change crack annealed glass [closed]

Over at Lifehacks.SE there is a question about how to remove ice from a windshield. One answer suggests using water but warns that using boiling water might crack the windshield. As far as I ...
1
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0answers
13 views

Fermi estimate for ice nucleation timescale

My friends in a Cryo-EM lab freeze their very samples quickly, a process they call vitrification. The timescale for this process is milliseconds (from wikipedia): The production of amorphous ice ...
0
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1answer
66 views

Stiffness in water

How do I find the stiffness or Fluid Elasticity for water (at a given temperature of for example 40 degrees)?
3
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1answer
154 views

Why do liquids form less bubbles when poured at an angle?

For example, I noticed that when I pour a soda on the side of a glass instead of directly into the cup, it forms less bubbles. This is also evident with rootbeer floats. Is this an actual scientific ...
1
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0answers
27 views

Do (or can) hydrogen bonds between water molecules neutralize their own polarity? [closed]

Do (or can) hydrogen bonds between water molecules neutralize their own polarity as indicated here: Hydrogen bonding as the mechanism that neutralizes $\mathrm{H_2 O}$ polarity ...
7
votes
2answers
188 views

Why does warm water sink?

It is well known that water at 4C is denser than water at 0C. This is the usual explanation for why a body of water freezes from the surface (also it's because ice is even less dense, but that's ...
0
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1answer
38 views

How can condensation be aided?

I was wondering if certain factors of water vapor condensation can be aided? For example, being able to increase the saturation of water vapor via a certain method, or another example would be having ...
1
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1answer
39 views

Why does liquid flow along the mug [duplicate]

I have been wondering why situation described in the picture below happens Why does the water/milk or any liquid poured from the mug/bottle flow along the surface of the vessel instead of leaving it ...
0
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1answer
36 views

How can we use conductivity measurements of water to find hydrogen ion concentration of water?

How can we use conductivity measurements of water to find the hydrogen ion ($\mathrm{H}^+$) concentration in water?
8
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2answers
649 views

Why things get dry (meaning from water)? [duplicate]

When I leave wet clothes in the open air, they will get dry over time by themselves even at room temperature. I know that somehow the water becomes vaporized; it's not "disappearing". For that, it ...
3
votes
1answer
392 views

Lifting a wet object off a table

When there is a film of water in between an object and the tabletop it rests on, it is difficult to pull the object directly upward. However, when you slide the object, it comes off easily. What is ...
1
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1answer
38 views

Water + RF + Spark = Continuous Fire

Can anyone explain the physics of what is happening in the following video? https://youtu.be/p8xYUDiSGDk?t=37 Is this process Radiolysis? At what radio frequency & power level is h20 ...
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1answer
108 views

Using water pressure as pushing force in a floating bath tub? [closed]

Does physics allow for water pressure to work in this way? if so What formula can prove this? (backup link 1, backup link 2)
1
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0answers
41 views

What is the maximum theoretical height upto which our oceans can rise? [closed]

The question is framed from a physics point of view so we will assume water is an indefinite resource. All I am interested in is if we go on adding water into our oceans then what is the maximum ...
1
vote
1answer
135 views

What actually makes boiling happen?

Boiling can be breezed over easily with a few rudimentary diagrams and a couple equations, but I seek a deeper explanation. The definition of boiling is that the vapor pressure in the liquid is ...
1
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2answers
81 views

How does calblock (water softener) work?

This "calblock" device claims to prevent limescale accumulation on water heaters in a washing machine. It sits between the water faucet and the washing machine; the water passes through it. I cannot ...
1
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2answers
137 views

Heat Losses from water pan due to vaporisation before boiling

I'm studying heat transfer from an electric heater to a cooking pan (Stainless steel) filled with water; specifically, my problem is related to water vaporisation, as I've already found good models to ...
3
votes
1answer
193 views

Sound waves creating bubbles in water

Sorry for the title, couldn't find a better one. A few years ago I read on a scientific magazine about a discovery, but I can't remember the name nor find anymore information on it. Basically they ...
0
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2answers
30 views

Increasing water temperature without salt

I have been extremely curious on how to get water even hotter by couple more degrees when its boiling. Rather then adding salt .... I started to stirring it.. Same Concept works with cooling the ...
5
votes
1answer
190 views

Why does a stream of water behave like this when aimed against a spoon or into a glass?

I noticed while doing everything except the dishes that water behaves quite strange. These two things might be two different phenomenon, but the water acts in a similar way in both cases. Spoon and ...
3
votes
2answers
72 views

Mirages under water?

In Polynesian shallow water, the temperature difference from short place to place is so high that one can see the same trouble refraction that exist in air above fire or metal sheet in summer. So I'm ...
0
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2answers
58 views

How much energy could be obtained by freezing water?

I know with our current technology energy is required to freeze water. But if the theories are correct we should be able to freeze water by extracting energy correct? How much energy could be ...
1
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0answers
24 views

Waterproof Case Time Limits [closed]

A lot of cellphone cases are rated safe for one hour at two meter depth. I assume this is due to water molecule diffusion along case seams (like the zipped zipper in a ziplock bag), right? Is ...
1
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0answers
84 views

standing waves on a cylindrical jet

as we know, there are some perturbations on a falling jet which are always present and according to their wave number and the radius of the jet, they can grow and decay over time. so, imagine a jet ...
0
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1answer
98 views

Can a hose filled with water go up if there is not a lot of pressure?

This might be more a general knowledge-type question or physics basics (or maybe not even physics) if so, I apologize and never took a physics class (my school never offered it), so I am not really ...