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## Main Question or Discussion Point

I am looking into hydrostatics, but am now very confused about what has to remain constant in an incompressible fluid. I initially thought that pressure has to be the same all throughout the fluid, and that this is the reason why you can use water or oil when raising a car- you apply a small force to a small area, and for the pressue to be the same as the fluid comes up on the other side there is a greater force exerted by this fluid on raising the car because the 'arm' has a greater cross-sectional area. So then the pressure would be the same throughout the pipe, but the force would not be.

However thinking about it in terms of work, when you have an incompressible fluid in a pipe which is initially wider but then it gets narrower, then the speed of the fluid in the narrower portion of the pipe must be greater. I was wondering about where the extra kinetic energy comes from, and I found this answer :

"That means that its kinetic energy is increasing. Where is it getting the energy from? The answer is that it can only do so if the pressure in the narrower pipe is lower than in the wider pipe."

Now I am really confused: is it pressure or force that is transmitted through an incompressible fluid, or neither?

Thank you :)

However thinking about it in terms of work, when you have an incompressible fluid in a pipe which is initially wider but then it gets narrower, then the speed of the fluid in the narrower portion of the pipe must be greater. I was wondering about where the extra kinetic energy comes from, and I found this answer :

"That means that its kinetic energy is increasing. Where is it getting the energy from? The answer is that it can only do so if the pressure in the narrower pipe is lower than in the wider pipe."

Now I am really confused: is it pressure or force that is transmitted through an incompressible fluid, or neither?

Thank you :)