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What they are doing in the video is heating up the liquid inside the vessel, (with an open lid). Then they take it out and immediately (i.e. before it cools down), they pack the lid. What happens is that as the liquid cools down, and the temperature (in Kelvin) drops then the pressure drops. An approximation is the ideal gas law (although as Abel pointed in ...


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Not checked out the video, but if you put a jar with a liftable lid in a vacuum sealer then as the pressure outside the jar is reduced air in the jar will push past the seal to equalize the pressure. Once the sealer is opened then as long as the jar seal is good the reduced pressure will stay in the jar.


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The problems with the vacuum would be that the resulting force would always be less than 1bar times the cross-section. In a typical dampener the pressure of the N2 (or compressed air) is a few bars, which results in a much more compact cross-section. It is difficult to maintain a vacuum Even if you could create a vacuum, it is very difficult to maintain ...


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Evacuating 10 psi of pressure from a 500 cu ft chamber in under a second is pretty insane. This is a good calculator, as you will probably need to change your parameters (most likely time) in order to find a suitable pump.


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They heat the jars and take them out of the oven open the lid to let the pressure out and then close it. Once the jar gets cooler the pressure inside that was occupied with hot expanded air settles and the air volume shrinks back causing it to create a small vacuum. Many times early in the chill mornings I see my bottle of water left in the cup holder ...


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As you have stated, a partial vacuum in the grey water space could be causing the water level in the pressure sensing tube to rise. It’s drawing water up the tube. The actuation level is probably set for atmospheric pressure in the grey chamber. Level Probe from Wikipedia


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Most car suspensions are based on a spring - used to be flat cart type but now most cars have coil springs. Some cars did go with a hydraulic suspension - early minis come to mind. If you really mean the shock absorber, or damper, then they can be pressurized and tend to use oil. Never seen a vacuum based system on trucks or cars but it might have been done -...


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What you are seeing in the video is a vacuum generator/vacuum ejector/aspirator. Figure 1: Venturi effect (source: wikipedia) It uses the principle of the Venturi effect. I.e. that for steady, incompressible, inviscid when there is an increase of speed there is a drop in static pressure. This is mathematically expressed as: $$p_1-p_2 =\frac{\rho}{2} (v_2^2- ...


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A pilot operated valve (often unfortunately generalized as a "solenoid valve") uses a small control solenoid valve and the pressure differential across the valve to open a diaphragm that allows flow to pass. This is a very common design because it allows for a large flow to be controlled with very little energy. This YouTube video has a good ...


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