New answers tagged fluid-statics
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Why is weight of water not considered in most situations?
When you're drawing the free body diagram, you're looking for forces that act on this body. Does the weight of water act on the body? It certainly acts on water, but does it act on the body?
If you're ...
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Why is weight of water not considered in most situations?
Not to be too pedantic about it, but: the weight of the water is a force acting on the water. In other words, it would be incorrect to view "the weight of the water" as force as acting on a ...
- 51.7k
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Why is weight of water not considered in most situations?
The "weight" of the water is covered for in the buoyancy force, so to say.
Water above the object pushes down on it with a force equal to its gravitational force (its weight). But other ...
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Hydrostatic equilibrium and fluid velocity
Equilibrium only means that net external force $\sum \vec{F}_{ext} = 0$ on the system. This means that the velocity $\vec{v}$ does not change with time, because there is no acceleration. This does not ...
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Does a pop pop boat work with vacuum above the water?
By way of example consider a pop pop boat with:
Exhaust outlet 3 metres below the lake level.
Boiler coil 1m above lake level.
Initially any water in the coil is vaporised and pushes any water out the ...
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How to derive the formula of the buoyant force?
First, let's derive the basic buoyancy equation.
The rectangle on the left represents a vertical cylinder of water of height $H$. The pressure ($P_H$) exerted at depth $H$ is equal to the weight of ...
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Inconsistent equations from two different references
Because any point in the same level must have the same hydrostatic pressure.
Is the premise true?
By subtracting twice the second equation from the first, we find that a=b, which means that the ...
- 28k
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Why do we consider only liquid-air surface forces in capillary rise?
I’m not an expert on this topic, but I’m gonna try to explain what I think is the answer to this question. First, notice how in the liquid-gas surface tension (the one we usually work with), the ...
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How smooth/rough is a liquid surface?
There are several theoretical models that can be used to make predictions about surface roughness. The most straightforward approach for liquid surfaces is to use statistical field theory with a ...
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