Will there be a capillary rise of liquid in vaccume with gravitation present?

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    Capillary Rise
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Discussion Overview

The discussion centers on whether liquid can experience capillary rise in a vacuum when gravitational forces are present. It explores the implications of surface tension, pressure differences, and the behavior of fluids in varying atmospheric conditions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants suggest that if the capillary fluid wets the walls, there could be a rise due to surface tension, which would balance with the weight of the fluid column.
  • Others question the conditions under which the fluid would rise in a vacuum, emphasizing the need for clarity on the pressure dynamics involved.
  • One participant raises the possibility of high vapor pressure fluids being incompatible with vacuum conditions, potentially affecting the experiment.
  • There is a reference to Einstein and a query about his potential contributions to the topic, with some expressing skepticism about the relevance of his work to classical fluid dynamics.
  • A later post clarifies the experimental setup involving a water container in a vacuum and questions whether the height of rise in the capillary tube would differ from that in atmospheric conditions.

Areas of Agreement / Disagreement

Participants express differing views on the mechanics of capillary rise in a vacuum, with no consensus reached on the conditions necessary for such a phenomenon or the implications of pressure differences.

Contextual Notes

Participants note the importance of understanding pressure differences at the same height in the capillary tube and the potential effects of fluid properties under vacuum conditions, but these aspects remain unresolved.

abhijitlohiya
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if gravitation is present, will there be a capillary rise of liquid in vaccume?
 
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Your question isn't clear.

If the capillary fluid 'wets' the capillary walls, there will be
a slight rise of the fluid due to the surface tension pulling the
fluid to adhere to more of the wall surface. When the
surface tension attraction force is balanced by the
force of weight of the lifted column the level will remain
at that point.

If you're talking about a manometer type of device, the
fluid will behave accordingly to the pressure difference
between the ambient pressure inlet port and the fluid
reservoir pressure i.e. the pressure on the other end of
the fluid column.

What would cause the fluid to rise if it were not vacuum?

What would cause the fluid to rise in the vacuum?

What would be the effect on the fluid if the device were
transported from a sea-level atmposphere environment
up to higher and higher altitudes until it was in a vacuum?

If the device works to measure something in a fashion
then that measurement process should apply continuously
over some range of measurements, with
vacuum (zero ambient pressure) being one ultimate case.

Of course some fluids have high vapor pressure in vacuum
at normal temperatures, so it's possible that the fluid
is not compatible with vacuum at the temperature you'd
be operating it... In fact the fluid would have to have
a significant surface tension otherwise it'd certainly
quickly 'boil' / 'evaporate' at comfortable temperatures in
vacuum.
 
didn't Einstein write a paper on this?
 
rewebster said:
didn't Einstein write a paper on this?

If so, I'm unaware of it, and wonder what his interest
would have been in the topic. It seems like something
that would be very straightforwardly explained by classical
hydraulics / gas law theories long before Einstein's time.

I know that fluid filled manometers were often used for
measuring pressures from atmospheric all the way down
to moderately high vacuum levels in lab settings,
and it wouldn't be uncommon to leave one connected
to one's vacuum system even once the pressure had
gone down to the point where the manometer wouldn't
be able to usefully measure it (p < 1 Torr).

Of course you'd need to use good vacuum pump oil or
mercury or something vacuum compatible in the tubes.
 
I mean if we keep a water container in vaccume and glass capillary tube is dipped in it will there be a rise of water in the capillary tube? If 'yes' is that height of rise same ,if the same expt is done outside the vaccume at the same place?
I am asking this because we explain the rise in capillary by considering the pressure difference at same distance above and below the liquid level in the capillary tube.
 

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