Bernoulli Eq vs General Formula: Pressure of Fluid

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The discussion centers on the apparent contradiction between Bernoulli's equation and the general pressure formula, where pressure is thought to be lower in smaller areas according to Bernoulli, while the general formula suggests higher pressure due to smaller area. It clarifies that in Bernoulli's equation, fluid flow is constant, not force, which explains the dynamics of pressure changes. The conversation distinguishes between static and dynamic pressure, emphasizing that Bernoulli's equation deals with dynamic pressure that varies with fluid speed. It also notes that for incompressible fluids, the relationship between flow area and pressure is more complex than simple force calculations. The participants express confusion about the factors affecting force and the implications of fluid behavior in different pipe sizes.
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According to Bernoulli eq Pressure of a fluid in a vertical pipe is lower where area is small.But from General formula P=F/A.Pressure should be higher.Isnt it a contradiction?
 
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Some fluids have minimal compression, like water. Two vertical pipes joined at the bottom with one smaller than the other would have movement.
 
Sorry I didnt get the point.Im assuming an incompressible fluid.
 
andytinker said:
Some fluids have minimal compression, like water. Two vertical pipes joined at the bottom with one smaller than the other would have movement.

?
 
moatasim23 said:
According to Bernoulli eq Pressure of a fluid in a vertical pipe is lower where area is small.But from General formula P=F/A.Pressure should be higher.Isnt it a contradiction?
It would be if F were a constant. In Bernoulli's equation it is the fluid flow that is constant, not the force
 
HallsofIvy said:
It would be if F were a constant. In Bernoulli's equation it is the fluid flow that is constant, not the force

Why F is not constant?On which factors does F depends here?
 
Is this explanation correct?
There are two types of pressures :
1)Static pressure
2)Dynamic pressure
In bernoullis eq we are talking about Dynamic pressure which increases or decreases wd fluid speed.
 
With minimal compression, the fluid doesn't follow PV=P1V1. If you have flow from a small section to large the pressure is lower, if its a compressible fluid that gets changed to velocity F=mv2, if its not velocity slows down.

I think
 
andytinker said:
With minimal compression, the fluid doesn't follow PV=P1V1. If you have flow from a small section to large the pressure is lower, if its a compressible fluid that gets changed to velocity F=mv2, if its not velocity slows down.

I think

I didnt get my answer.:(
 

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