Fluid statics or hydrostatics is the branch of fluid mechanics which deals with the study of fluids at rest and the pressure exerted by it on an immersed object. If your question is about the study of fluids in motion, use the tag "fluid-dynamics" instead.
Questions tagged [fluid-statics]
1750 questions
124
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9 answers
Why does a helium filled balloon move forward in a car when the car is accelerating?
I noticed that when I had a helium filled, latex balloon inside of my car, it moved forward in the cabin as I accelerated forward. The faster I accelerated forward, the faster the balloon went from the back of the car to the front of the car. The…
user33986
- 1,209
72
votes
3 answers
Why is dry soil hydrophobic? Bad gardener paradox
When I forget to water my plants, and their soil becomes very dry, during the next watering I can see that the soil becomes hydrophobic. I can even see pockets of air between the repelled blob of water and the soil.
On the contrary, when the soil is…
user46147
- 3,114
59
votes
7 answers
Is the weight of the aircraft flying in the sky transferred to the ground?
Is the weight of the aircraft flying in the sky transferred to the ground? Is the weight of people swimming in the pool also transferred to the ground? How can we prove it?
enbin
- 2,306
58
votes
8 answers
Given that ice is less dense than water, why doesn't it sit completely atop water (rather than slightly submerged)?
E.g.
If we had a jar of marbles or something else of different densities and shook it, the most dense ones would go to the bottom and the less dense ones to the top.
(Image Source)
If I put a cube of lead in water it would sink all the way to the…
K-Feldspar
- 1,377
56
votes
3 answers
Why doesn't this perpetual motion machine using the buoyant force work?
I realize this isn't possible, but I can't see why not, especially if you change the model a little bit so that the balls simply travel through a tube of water on the way up, rather than exactly this model.
Please be clear and detailed. I've heard…
Martin
- 579
55
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4 answers
Why does a cup with 100 g water float when placed on another cup with 50 g of water?
Imagine we have cup A with 50 g of water and cup B (smaller in width than A) with 100 g of water. Now put cup B into cup A. If the width of both cups are of comparable size then the cup with 100 g of water floats. It does not touch the bottom of cup…
quantum
- 531
49
votes
6 answers
Does the sea level increase if an iceberg melts?
It was claimed that if an iceberg melts in the ocean, the sea level won't change as the ice displaces as much water as there will be melted water. The other claim was that the sea level should rise because oceans contain salt, so the water in oceans…
Jaakko Seppälä
- 641
47
votes
6 answers
Why do rotten eggs float in water?
My mom told me that one can check whether an egg is rotten by sinking it in a glass of water. If it floats, then it is rotten.
I didn't find any explanation for this phenomenon. If anyone knows one, please answer.
prAnjal
- 593
42
votes
4 answers
Will a penny ever stand still in the water at a certain depth?
Let’s say I drop a penny in the deepest part of the ocean having a certain depth. Would the penny become buoyant enough to stand still in the water, since the density of water increases with depth? Since the buoyancy of objects becomes greater as…
Justus Bozzi
- 445
41
votes
3 answers
Can ants walk on liquid mercury?
I'm not a physicist, but I was wondering:
Can ants walk on dense liquid like mercury and why?
Apolo
- 513
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39
votes
8 answers
Can a battleship float in a tiny amount of water?
Given a battleship, suppose we construct a tub with exactly the same shape as the hull of the battleship, but 3 cm larger. We fill the tub with just enough water to equal the volume of space between the hull and the tub. Now, we very carefully lower…
SlowMagic
- 1,053
36
votes
4 answers
What really is a fluid?
My question may be pretty basic, but I feel it is important to ask this as I've gone through several texts and none offer me the clarity I seek.
The question is: What is a fluid? What is flow? If we say that a fluid is something that flows, the next…
stoic-santiago
- 1,961
35
votes
4 answers
What is the energy source if a tall water tank is used to transfer floating objects upwards instead of cables with motors?
Suppose I want to transport some logs from the ground to the roof of a tower. Originally I can use a lift, or some cables, or even move the logs upwards manually; then the energy is converted to the potential energy of logs.
Now, if I build a tall…
Gstestso
- 917
34
votes
4 answers
Why does a cork float to the side of a glass?
Why does a cork ball float to the side of a glass as illustrated in the following GIF? What is the physical phenomenon behind this observation and why does it happen?
Mohammad Fakhrey
- 839
32
votes
6 answers
Why should water fall down from an upside down glass of water?
Suppose I have an upside down glass of water that I somehow brought in the configuration shown below (without any air between the glass and water). Now the water will obviously fall down but my question is why exactly?
The forces on the water column…
FullBridge
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