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CherryB
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- When I opened the atmospheric inlet the bellows extended only when there was water inside. I think that the weight of the water is causing that, but why?
the top valve (Valve 1) is about 12 inches from the surface, while Valve 2 starts out 20" away and ends up 32" away, falling a total of 12"Baluncore said:What are the maximum and minimum depths from the surface to the bottom valve 2.
The valve is attached to the bottom of the bellows and the bellows extend and contract, so the valve can move. There was water already inside the bellows, both valves were closed and the bellows were in their retracted position. The valve itself is denser than water, so it readily sinks, and when the top valve is opened to the atmosphere, the bellows descended and sucked air in as they fell. I did not think they would fall, and that's what is puzzling to me. I thought the water would push against the bottom of the bellows and would not allow them to fallkuruman said:Is the valve attached to something that prevents it from moving relative to the water? If so, there would be a buoyant force that compresses the bellows when there is no water in the valve. This explanation assumes that the bellows is extended when it's out of the water.
But isn't the water pressure from below stronger than the atmospheric pressure from above?hmmm27 said:There's really not a lot to consider : displacement of the apparatus vs. weight of the apparatus, and any springiness the bellows have,
I agree. Suppose one fills the bellows with water while compressing them relative to their relaxed position and then closes the top valve. When released, the springiness of the bellows would cause them to extend a bit but that would create a partial vacuum inside which would prevent the bellows from extending fully. When the top valve is opened, the inside and outside pressure are equalized as air is sucked in.hmmm27 said:There's really not a lot to consider : displacement of the apparatus vs. weight of the apparatus, and any springiness the bellows have,
Is it possible that there was partial vacuum in the heat space above the water in the bellows?CherryB said:I really appreciate all the feedback! I don't know the internal pressures, Chestermiller, as I did not have gauges in use. The bellows have a pretty strong spine that would keep them from being crushed by the hydrostatic force, but would allow them to be compressed through their length, so I would assume that the pressure inside would have to be pretty close, if not equal, to the pressure outside when full of water, but I am not sure about that pressure when full of air, because I was only allowing atmospheric air to sucked in vs pumped in.
Hydrostatic pressure is the force exerted by a fluid at rest, while gravity is the force that pulls objects towards each other. Hydrostatic pressure is caused by the weight of the fluid above a certain point, while gravity is a fundamental force of nature that affects all objects with mass.
Hydrostatic pressure increases with depth, so objects underwater experience more pressure at greater depths. This can cause compression of objects and can also affect the buoyancy of objects, making them easier or harder to move through the water.
Gravity plays a crucial role in the movement of fluids, as it causes fluids to flow from areas of high pressure to areas of low pressure. This is known as the pressure gradient force. Gravity also affects the density of fluids, which can impact their movement and behavior.
Yes, in certain situations, hydrostatic pressure and gravity can be balanced. This is known as hydrostatic equilibrium, where the pressure of the fluid is equal in all directions and there is no net force acting on an object. This can occur in the ocean, where the weight of the water above is balanced by the upward force of the water below.
Hydrostatic pressure and gravity have many practical applications, such as in hydraulic systems, where the pressure of a fluid is used to transmit force and energy. They are also important in industries such as oil and gas, where hydrostatic pressure is used to measure the depth of oil wells. Gravity is also used in various technologies, such as satellites and rockets, for navigation and propulsion.