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### Author Topic: Thought Experiment - Is An Endless Siphon Possible?  (Read 2594 times)

#### Aemilius

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##### Thought Experiment - Is An Endless Siphon Possible?
« on: 14/07/2013 00:22:26 »
Is magnetically enabled continuous circulation of a diamagnetic fluid possible?

Here's a thought experiment wherein an inverted U shaped tube formed of two branches of unequal length can transfer fluid from a higher level to a lower level within a single resevoir over an intermediate elevation by the force of excess of weight of the fluid in the longer branch which, when once filled, causes a continuous flow and pressure of the atmosphere in forcing the fluid up the shorter branch of the tube immersed in it at reduced pressure.

Since the end of the left tube is lower than where the right tube enters the fluid, per the simplified approximate hydrostatic pressure equation, there will be pressure difference, P=hpg, where h is the height difference, P the density of the fluid and g the acceleration of gravity. So fluid will flow from the right end of the tube to the left end. Because the tube is higher in places than the fluid surface, this is called a siphon. As long as there’s a height difference, there will continue to be pressure, and right-to-left flow.

The question is.... After the experiment starts by exposing the left end of the siphon (full of fluid) to atmospheric pressure, what condition will the system be in? Will fluid in this system flow indefinitely?
« Last Edit: 17/03/2014 19:45:47 by Aemilius »

#### RD

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##### Re: Thought Experiment - Is An Endless Siphon Possible?
« Reply #1 on: 14/07/2013 09:29:47 »
If the magnet was strong enough to deform the surface of the water it would also apply forces to the water in the siphon preventing  the siphon from working.
« Last Edit: 14/07/2013 09:38:47 by RD »

#### Aemilius

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##### Re: Thought Experiment - Is An Endless Siphon Possible?
« Reply #2 on: 17/03/2014 19:54:08 »

#### chiralSPO

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##### Re: Thought Experiment - Is An Endless Siphon Possible?
« Reply #3 on: 20/03/2014 16:49:34 »
RD is definitely correct.

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##### Re: Thought Experiment - Is An Endless Siphon Possible?
« Reply #3 on: 20/03/2014 16:49:34 »