Questions tagged [water]
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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2answers
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Does the mass of a beaker filled with water change due to a mass partially submerged in it?
I believe it should be different as there is upthrust acting on the second block and hence by Newton Third's Law it should act back on the liquid adding to more weight. The answer is given isn't so as ...
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1answer
40 views
Microwaves and Water Molecules: Radar vs Cooking
I am studying microwave radiometry and confused over this apparent contradiction: Microwaves emitted at 2.45 GHz (~15 cm) are absorbed by water molecules, causing the molecules to rotate under the ...
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1answer
29 views
Why is it easier to catch mosquitoes with your hand when your hand is wet?
Recently I've noticed that it's significantly easier for me to catch a mosquito with my hand if my hand is very wet (e.g. from having washed my hands and not yet dried them, or from being in the ...
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1answer
23 views
Sound made by trapped water
When I run water in my bathroom sink and then put the plug in whilst there is still some water left in the basin, there is a high pitch moaning or screeching noise made by my adding the plug. What ...
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0answers
26 views
Snow without sunlight [on hold]
I just saw an ad for a certain mobile game. The sun was obstructed by some machines. And there was snow and wind blowing. The snow: My theory is that snow couldn't have been formed, because the were ...
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0answers
15 views
Calculate water points positions from Navier-Stokes equations [closed]
I am writing a physics simulation of water using shaders and Unity3D, and I think Navier-Stokes equations are pretty good fit for that task. I have low math knowledge, so it's hard for me to ...
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1answer
68 views
Did the Chernobyl power station's water cistern really hold $7000\:\rm m^3$? [closed]
In he HBO TV miniseries Chernobyl, they talk about a cistern holding 7000 cubic meters of water. That is the content of Loch Ness, the deepest lake in the UK. Would the Chernobyl reactor really hold ...
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1answer
24 views
Relation between rain, time and terrains
I would like to understand whether an approximate relation between the rain and the physical properties of a particular terrain (composed of a specific material such as asphalt or clay or grass or ...
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1answer
37 views
Why does a cup on water layer create suction?
When I place a cup upside down on a layer of water, say a wet table, and I then try to lift the cup up, I can feel some resistance. So the cup is acting like a suction cup.
However the difference is ...
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0answers
31 views
How is reverse osmosis even possible for desalination?
I don't understand how reverse osmosis for desalination is possible for existing RO membranes of pore size 10 angstroms (A) if the radius of a sodium atom is 3.14 A, chloride is 3.7 A and maximum ...
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1answer
44 views
How does an ultrasonic humidifier / atomizer affect temperature?
Evaporative cooling is a technique used to cool air by using the evaporation of a liquid.
My google research on evaporative cooling shows a ubiquitous concept of forcing air through a pad/membrane/...
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0answers
14 views
Underwater acoustics: particle motion
The properties of an acoustic wave field depend on the mechanical properties of the supporting medium, including the density, and the bulk modulus. With increasing density, the propagation speed of ...
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1answer
49 views
When I do water electrolysis, which water molecules are split apart?
If I do water electrolysis I will get hydrogen at one electrode and oxygen at the other.
Is it because a molecule of water somewhere in the middle splits into H and O and then the H and O travel to ...
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0answers
22 views
Is it possible to calculate force acting on water in electric field?
I know, that when water is placed in an electric field a force is acting on it because of polarization. Is it possible to calculate this force with taking the brownian rotation of the molecules as ...
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1answer
75 views
Why do we heat salt water to desalinate it rather than freeze it?
Most sea water desalination plants rely on the basic principle of heating water to evaporate it, after which the salt-free vapor is condensed. According to Wikipedia, over half the cost of ...
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0answers
215 views
Risk of megaton steam explosion from Chernobyl? [duplicate]
In the new Chernobyl TV series (https://en.wikipedia.org/wiki/Chernobyl_(miniseries)), in episode 2, there's a reference to the risk of a steam explosion from the molten reactor core entering a water ...
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1answer
30 views
Will we be able to experience huge waves one after the other if we were near a strong gravitational field?
I was wondering if we will have huge waves due to the presence of a strong gravitational field nearby earth?
If our planet is rotating around the gravitational field, is there a possibility for ...
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1answer
72 views
Grooves on water tank
Why are there grooves on almost every water tank?
Just typing water tank in Google images would reveal what I am talking about. And here is a sample picture!
I think it would mostly be regarding ...
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2answers
55 views
Minimal work required to produce ice at room temperature
I'm wondering about the most efficient way of producing ice from water at room temperature.
First of all: why, in principle, do we need to put in work to do so, if water gives off energy while ...
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2answers
50 views
Water thru a small hole
If I were to fill a 700c 25mm road bike tire with some water and pump the tire to, say 100psi, and punch a tiny hole in the tire, the water will start to spray out.
My question is: does the water ...
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2answers
36 views
Styrofoam planted in iron, can it float
Imagine a cube Styrofoam box planted in an iron box with the same size, if we put it on the water
Can it float?
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1answer
40 views
Hydrostatic pressure to measure water level
I am measuring water level in a 25-inch tall vase using hydrostatic pressure. Like this.
To do this I have a 1/4 OD inch nylon tube connected to a gauge pressure transducer. So far it has been very ...
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1answer
22 views
Hot Tub Heating - Element Size
Is it more cost effective to heat a hot tub with a smaller heater, say 1.5kw, than it is to heat it with a 3kw heater or even a 6kw heater?
Obviously the larger heaters will heat the water faster - I ...
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2answers
68 views
Real world applications of triple point?
What are the real world applications of triple of water? And is it worth researching what factors could effect it?
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4answers
5k views
Will tsunami waves travel forever if there was no land?
If there was no land for tsunami waves to collide with, can the waves travel around the globe for forever?
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3answers
1k views
Does tea made with boiling water cool faster than tea made with boiled (but still hot) water?
I always make tea with boiling water - not water that is almost boiling, not water that has boiled and stopped boiling a few seconds earlier - in my opinion, for the best tea flavour the water must be ...
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1answer
76 views
What would happen to the water bodies if gravity ceased to exist on Earth?
If water stopped flowing (it would stop flowing downwards from mountains and all)
then, would it start rising upwards? If it floats on the space ( I say space because there'd not be any atmosphere) ...
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0answers
32 views
Sensitivity of latent heat of fusion of ice on temperature and pressure
The enthalpy of fusion is the heat necessary to convert 1 kg of ice to liquid water. According to Wikipedia, this heat equals 333,55 kJ/kg.
Does this heat change with the temperature or pressure and ...
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2answers
76 views
How many calories of energy does it take to heat up 1 cubic inch of water 1 degree Fahrenheit? [closed]
In metric, one milliliter of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to heat up by one degree centigrade--which is 1 percent of the difference between ...
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0answers
16 views
Is there any force that affect to wearable accelerometer underwater?
I am trying to find displacement of underwater sport player with my accelerometer sensor. My question is; is there any force that affect to an object that weared by a human underwater? Thanks.
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0answers
42 views
Can water be made more violet?
Water is intrinsically blue because of molecular vibrations. The topic is covered here: Only sea water appears blue in color, why this is not happening in river water?
And here, which I post ...
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0answers
48 views
Moonlight reflection on ocean [duplicate]
I am trying to explain physically what is happening in the picture below:
My gut explanation is that we are observing the reflection of a cone of light emanating from the moon, it explains the form ...
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2answers
84 views
Density of ice < water?
In the situation of an ice cube placed in water and eventually melting, it is supposed that natural convection is the process in which heat transfer from water to ice occurs.
However, natural ...
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4answers
786 views
How does ice melt when immersed in water?
When an ice cube is immersed in water at a room temperature, how is the thermal energy from the water transferred to the ice cube?
Currently I have two answers:
Infrared radiation from the water ...
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0answers
30 views
Velocity of a leak in a cylindrical water tank that spins with constant angular velocity
We have a cylindrical water tank that spins over its axis of symmetry. Here's a diagram:
The objective is to find:
$1$ - The tangential and radial components of the velocity of the water as it ...
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1answer
38 views
Does light only mimic water waves, or also the properties of water?
Huygen's Principle compares diffraction to ripples in water. Do the similarities translate to surface tension? The hydrophobic effect?
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2answers
48 views
Is there any reason to remove the air from a bottle of water before you freeze it?
When you put a sealed bottle of water in the freezer it explodes, (I get this part). I was told that filling it with 100% water (removing the air) first stops the bottle from exploding as this allows ...
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1answer
612 views
Does soap repel water?
Yesterday when I was taking my bath, I scratched my soap bar a bit and threw that bit on the shower floor. There was a little amount of water on the floor where that soap bit fell. To my surprise, I ...
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1answer
28 views
How does waterfall produces negative ions? Do rain do too?
I read that water molecule steal electron from oxygen molecule but the next sentences onward is talking about the benefit of negative ions for health, what is the cause of negative ion production in ...
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0answers
74 views
How long would it take for a cup of water to fully evaporate?
How long does it take for a cup of water to evaporate?
To answer this question, I'll assume some basic parameters, and that the water is blown on by a fan, to arrive at an estimate:
Water volume: $...
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1answer
86 views
Why microwave oven makes dried bread soft?
This is an old age trick: if you have some bread that became dried and you put it in the microwave few tens of seconds (10 to 30 for top results) you get a nice soft and warm loaf as if it just came ...
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0answers
36 views
Measure static pressure with measuring tubes of different diameter
Assume you have a horizontally placed cylindrical pipe with constant diameter. There is a flow of water, through this pipe. You want to measure the static pressure inside the tube, which should be the ...
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1answer
56 views
Water and Resonance
I want to confirm this, I’m not 100% sure on the subject and I’ve done a lot of research into this. Does water not only take the shape of the vessel it’s in but also the frequency and or resonance.
...
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1answer
55 views
Phase change in oceans
When ice cube melts in water the level of water doesn't change but when glaciers melts in oceans sea water level increases why?
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0answers
50 views
Do quantum effects play a role in the evaporation of water?
Imagine a thermodynamic system composed of a tumbler half-full of pure water, composed entirely of 1H and 16O. The system is isolated from extraneous influences by a perfect box impermeable to ...
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2answers
81 views
The maximum velocity of an object in water [closed]
Suppose we have the mass and volume of an object, like a sphere, with density less than water. We grab it under the water and leave it, so it will fly up to the surface. What will be the maximum ...
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1answer
41 views
Maximum density of water
The maximum density of water in its liquid form occurs at around 4°C (under normal pressure p = 1013,25 hPa). If the pressure is increased (or decreased) would the point of maximum density still be at ...
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1answer
50 views
Converting normal water into magnetic water [closed]
When I magnetize water by circular magnets of strength 0.8 T, how long will the magnetism be present in the water? I mean, how many days will it be in the water?
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0answers
19 views
Why sand in a water collects at center on rotating the water? [duplicate]
We commonly observe that on rotating dirty water, the dirt in water collects at the center. But why does it happens, and why does it not collect at edges due to centrifugal force. Does something ...
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1answer
60 views
Microwaves in other media
I saw a video on how microwaving grapes make plasma. He said that the refractive index of microwave is about 10 inside the grape. Now, we don't know the wavelength of the microwaves in the grape or ...
