Tagged Questions
2
votes
0answers
41 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.
...
6
votes
2answers
148 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
2answers
106 views
Best shape to reduce the splash of a droplet?
Our coffee machine catches the last couple of droplets, after your cup is removed on a shape to reduce plash of the coffee droplets.
These shapes are placed inside the spill reservoir.
The shape ...
3
votes
2answers
110 views
Pumping water from a closed column. Will the column get empty or just circualte?
As a picture is worth a thousand words, here is my problem:
It is a closed water column with a bit of air in the top section.
If I run the pump and make the water flow from IN to OUT,
Will the ...
1
vote
1answer
132 views
How fast does water fall in the middle of a very very thick waterfall?
Let me create a very artificial experimental set up. Take a bathtub the size of Delaware and suspend it a mile above the ground. Fill it with water (though I'm not sure to what depth - and it might ...
4
votes
3answers
186 views
How can I keep a smaller water reservoir's water level at half available when being fed from a larger reservoir? [closed]
I'm trying to create my own ultrasonic humidifier. I ordered the misting part which works great but it only functions correctly in shallow water. So I'd like to feed from a large water reservoir to a ...
0
votes
1answer
82 views
Measure maximum volume of liquid of a water tap
I need to know the consumption of a water tap in Liters.
I'm able to know the cross-sectional area of the pipe and how long the tap is open. With these data, how can I know the consumption/volume of ...
4
votes
1answer
165 views
Can you measure the speed of water coming out of a hose by its arc?
Water comes out of a horizontally stationed hose and creates an arc as it heads towards the ground. Can I determine the speed the water was traveling in when it exited the hose by the measuring the ...
1
vote
1answer
220 views
Pump pressure required to fill water tower
I have a water pump at a distance of x meters from a water tower located h meters above the pump through a pipe with diameter d. I am not concerned with the exact value just want to make sure my pump ...
4
votes
4answers
437 views
How far can water rise above the edge of a glass?
When you fill a glass with water, water forms a concave meniscus with constant contact angle $\theta$ (typically $\theta=20^\circ$ for tap water):
Once you reach the top of the glass, the water-air ...
2
votes
2answers
230 views
Will the siphoning effect help a system pump water upwards if the water's entry and exit points are at the same height?
I am looking to pump water from a pool up to a roof for solar heating (black plastic tubing) and then back into the pool with the original source water. Does the gravitational force of the water ...
3
votes
2answers
307 views
Why water is not superfluid?
My question is in the title. I do not really understand why water is not a superfluid. Maybe I make a mistake but the fact that water is not suprfluid comes from the fact that the elementary ...
1
vote
2answers
155 views
Fluid Dynamics - Water Bottle Drink Mix: Air or No Air?
If you take an ordinary sized plastic water bottle full of water and pour a packet of powdered (or liquid) drink mix into it, Will shaking the bottle with the cap screwed on to dissolve the mix into ...
0
votes
0answers
130 views
Reduction in velocity in pipe
I have two pipes divided from main pipe. If I add one more pipe, what would be the amount of velocity in each pipes. I know the velocity of main pipe, then diameter and radius of each pipe.
Edit:
1) ...
7
votes
5answers
317 views
Zigzag flow of water along a vertical glass window
I've observed this behavior many times. When it rains, the rainwater will form vertical channels along a glass window. The flow of water is mostly confined within these vertical channels and the ...
0
votes
1answer
75 views
how to stop water reaching up inside an under water structure (see video)
in this video at arround 0:47 they deliver the 'dry pots' to the under water lab, bellow the water and they seem to swim up into an opening where it is completly dry.. how is this dry, surly the water ...
4
votes
2answers
2k 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 ...
1
vote
1answer
119 views
How would this rapid depressurization of water really behave?
An in-development game(Starbound) recently released a demo of their water physics. At about 39 seconds into the video, a volume of water in a container is released when the cap on the container is ...
8
votes
1answer
723 views
Why does water flow out of an upside-down bottle? (Rayleigh Taylor Instability)
I am currently reading the excellent book An Indispensable Truth: How Fusion Power Can Save the Planet by Francis F. Chen and I came across this explanation.
The Rayleigh–Taylor Instability
...
2
votes
1answer
412 views
How much water must flow trough canal to maintain a constant water deep?
In order to maintain a constant water deep in canal, how much water must flow trought the pipe ?
As shown on picture, canal have a rectangular shape.
I don't know if canal length have an influence.
...
4
votes
2answers
2k views
Why does water pouring from a glass sometimes travel down the side of the glass?
If you have a glass of water, say, three quarters full and you pour it at an angle of say, $45^{\circ}$ with respect to the the table, the water comes out of the glass and goes directly down towards ...
1
vote
3answers
8k views
Relation between water flow and pressure
Is there any equation that states the relation between pressure and water flow.
I.e. Let's say that in 1 hour with 8mca (water collum meters) pressure I obtain 50m3. What if (giving the same ...
23
votes
2answers
2k views
Before a once-warm lake starts to freeze, must its temperature be 4°C throughout at some point?
This is a problem I just started puzzling over, and I felt this would be a good forum to check my reasoning. So here are the relevant observations followed by my question:
Water achieves its maximum ...
2
votes
1answer
558 views
static flow of water
The title, I don't know whether it's correct or not, but I came across a video in youtube, http://youtu.be/_PkgQQqpH2M.
The author of video used the title and hence I used the same..
The video ...
5
votes
2answers
108 views
Wave with mass transport?
I don't think this question has been asked on this forum before (at least I didn't find it).
In the case of a tsunami, an earthquake generates a wave which will travel with the sea/ocean as the ...
1
vote
1answer
225 views
How to model water flow with and without friction against other objects?
I am interested in modeling water flow including boundary flow (with friction) against other objects in the path of the water flow.
I'm not a physicist but I am interested to learn the relevant ...
0
votes
1answer
175 views
I want to recreate a phenomenon I've noticed from our water tank
I'm trying to recreate a phenomenon I have noticed from our water tank at home. Ok so we have a deep well pump that fills our water tank everyday. But something odd always happen everytime the water ...
2
votes
1answer
243 views
Calculating spacecraft water leak flow rate
A large container of heated water is floating in space. How can I calculate leak rate if a small puncture is opened?
I'm assuming the water is kept at 298K and in the liquid state inside the chamber.
...
2
votes
1answer
99 views
Clouds in closed hydrosphere
Is possible estimate the needed size of an geodesic dome (like in the Eden project) for creating an real hydrosphere - especially clouds (and rain)?
With other words, under what circumstances can ...
11
votes
2answers
664 views
Why doesn't water come out of tap/faucet at high pressure when I turn it on?
(tap=faucet)
When I turn a tap on full and then put my thumb over the spout covering, say, 90% of it, then the water spurts out. If I turn it on to, say 10%, then the water dribbles out.
What's the ...
2
votes
2answers
207 views
Water and superconductors
If you have seen my previous questions then this may make better sense. If you put an insanely powerful superconducter on the outside layer of a ROV that is underwater, would it form an outer layer ...
3
votes
1answer
251 views
Tear drop shape
i heard that a tear drop shap is the most aerodynamic shape possible or the best is this true? If this isn't true what is since i need to make a fast ROV? Also since i need to have a propeller to ...
2
votes
3answers
197 views
can Superconductivity be used to repel water?
Can water be repeled with the force from superconductivity gathering current on the surface cuased by Faraday law of induction? I'm trying to make a ROV that can run underwater that uses ...
1
vote
1answer
148 views
Surface Tension of a Liquid - When a liquid body is acclerating
As far as I understand it (which admittedly isn't very far), surface tension forces are made up by the tension-attractive forces of molecules at the liquid-gas/vacuum interface, such as those between ...
8
votes
5answers
337 views
What can wavy patterned sand tell about the Fluid that formed it?
Sand on the bottom of the ocean as well as sand on the low-tide beach often forms wavy patterns. Do the parameters of these wavy patterns have any relation to the water and waves that formed them? If ...
2
votes
2answers
617 views
How to calculate concentration of vapor at the surface of a water drop
I'm reading a paper that examines the evaporation rates of water. In the final formula, it has the following constant:
$c_s - c_\infty $ where $c_s$ is the concentration of the vapor at the sphere ...
2
votes
1answer
386 views
Water droplet evaporation due to humidity and temperature
I am conducting an experiment that requires comparison to models for a water droplet's change in size due to evaporation. I've found plenty of papers, but they all seem to require measurement of the ...
2
votes
2answers
350 views
the form of a kettle
What is the best form for a kettle, that is, to have the water boil the fastest? I am particularly interested in the following case: for one given kettle (whose volume is constant) containing ...
7
votes
1answer
743 views
water flow in a sink
When one turns on the tap in the kitchen, a circle is observable in the water flowing in the sink. The circle is the boundary between laminar and turbulent flow of the water (maybe this is the wrong ...
5
votes
1answer
168 views
Resonance modes of a cubic box of water which we shake
I don't know hydrodynamics, but I wonder how one would compute resonance modes of a cubic box of water which we shake. I believe the waves would directly depend on the height of water and the width ...
6
votes
3answers
2k views
Why does the water level equalize in a series of tubes?
Say I have a series of tubes (not the internet) looking like this, where w represents water:
...
