Tagged Questions
0
votes
1answer
50 views
Absorption of Water
I was just watching the videos Chris Hadfield put on youtube from space, and was wondering why water doesn't get absorbed as well onto his toothbrush in space?
And what characteristic of ...
3
votes
0answers
54 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.
...
0
votes
0answers
62 views
Water evaporation
It is known that molecules at the surface are strongly attached to each other (more attraction less repulsion) than those within the bulk attraction and repulsion are balanced). This is the molecular ...
43
votes
3answers
1k views
What causes insects to cast large shadows from where their feet are?
I recently stumbled upon this interesting image of a wasp, floating on water:
Assuming this isn't photoshopped, I have a couple of questions:
Why do you see its image like that (what's the ...
4
votes
4answers
484 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 ...
5
votes
1answer
167 views
Distinctive properties of liquids
The molecules are closely arranged in solids, loosely arranged in liquids and are free to move in gases... But, Why are liquids (especially water) exhibiting these distinctive properties such as ...
7
votes
5answers
332 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 ...
8
votes
1answer
780 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
...
6
votes
3answers
2k views
Why does a bullet bounce off water?
It is known that bullets can ricochet off a body of water. Is surface tension responsible for this or is this the same behavior we see when an asteroid ricochets off the atmosphere? I don't think ...
3
votes
1answer
696 views
Cooking pasta: why does adding a lid lead to overflow?
When cooking pasta, some organic foam usually forms on the surface of the boiling water and the situation can be kept under control by adjusting the heat (and/or adding some oil).
Covering the pot ...
1
vote
1answer
150 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 ...
