Holding Water in glass upside down

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Discussion Overview

The discussion revolves around the feasibility of holding water in a glass upside down, particularly without the aid of paper or other materials. Participants explore the physics behind this phenomenon, questioning whether it can be achieved through surface tension or if it is merely a trick.

Discussion Character

  • Exploratory
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • Some participants express skepticism about the possibility of holding water upside down without paper, suggesting it may be a trick.
  • Others propose that surface tension alone is insufficient to hold the water in place, questioning the physics involved.
  • A few participants mention that using a mason jar with a screen can facilitate the trick, indicating a possible method to achieve the effect.
  • Some contributors share their personal experiments with various glass types, noting failures to replicate the effect without additional support.
  • One participant reflects on their initial belief that pressure and water weight could suffice, admitting to being wrong after multiple attempts.
  • There is mention of the performer in the video possibly using a hidden support to achieve the illusion, with suggestions for alternative materials that could be used.

Areas of Agreement / Disagreement

Participants generally disagree on whether the effect can be achieved without additional materials, with some believing it is a trick while others explore the physics behind it. The discussion remains unresolved, with multiple competing views present.

Contextual Notes

Participants note limitations in their experiments, such as the diameter of the glass rim affecting outcomes and the dependence on specific materials to achieve the desired effect. There is also an acknowledgment of the potential for misinterpretation of the trick in the video.

Who May Find This Useful

This discussion may be of interest to those exploring physics concepts related to fluid dynamics, surface tension, and experimental methods in a practical context.

I_am_learning
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With the paper it can work, but without paper, I highly doubt it?
Give me some 'physics' reason why it should/shouldn't work.
http://www.youtube.com/watch?v=3rY0auw5wCo&feature=relmfu

P.S. How do I embed video? Youtube tag isn't working.
 
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Give me some 'physics' reason why it should/shouldn't work.

You cam't be serious! It is a trick - magic. You want an explanation how to do the trick?
 
Without the paper in place, that's got to be a trick, surely? The surface tension of the water isn't enough to hold it in place, is it? Or is it?

Edit - I've been practicing, and run out of dry card to use, but haven't made it work so far. I'll let you know if I get a positive result!
 
Last edited:
Rooted said:
Without the paper in place, that's got to be a trick, surely? The surface tension of the water isn't enough to hold it in place, is it? Or is it?

Edit - I've been practicing, and run out of dry card to use, but haven't made it work so far. I'll let you know if I get a positive result!

You are wasting your time, unless you use a glass with a very, very small diameter rim.

The paper part is easily expalined by physics, as noted above.

The part without the paper is the trick part. Re-run the video, but this time notice how the performer picks up the paper. He does not show you the bottom. Notice how his thumb is underneath as if to hold something else against the paper. Notice how he wiggles the paper so that the something else will neatly and snuggly fit just inside the rim so as to unseen. Turn the glass upsied down, gently remove the paper and the something else holds the water inside the glass. Same physics apply. Try a reasonably rigid clear sheet of plastic with a diameter just slightly less than the diameter of the rim. Clear is what makes it a trick, but any color will do if you are not ding a magic show.
 
256bits said:
You are wasting your time, unless you use a glass with a very, very small diameter rim.

Good, I am glad about that. I have been experimenting with narrow glasses, including shot glasses and latterly a test tube with the name of a popular alcoholic beverage written on the side, and all have yielded negative results. I am quite pleased really that something that appeared unphysical on first viewing still appears that way on testing. Although secretly I was hoping for a positive result that would throw all my physics instincts out the window. Ah, the joys of science.
 
I believed the same pressure that held the paper plus the weight of the water would be enough to hold the water alone. I was wrong. How embarrassing! I too tried this dozens of times but couldn't get it to work. As 256bits mentions, you can see him fitting something into the rim of the glass. This does work with a mesh screen though.
 
Jimmy said:
I believed the same pressure that held the paper plus the weight of the water would be enough to hold the water alone. I was wrong. How embarrassing! I too tried this dozens of times but couldn't get it to work. As 256bits mentions, you can see him fitting something into the rim of the glass. This does work with a mesh screen though.

I so wanted to believe it too. I suppose if it had worked it would be potentially possible to drink from the cup upside down, which would be more blatantly impossible. Still, as it stands its a great party trick. I wonder how many laptops have died this way?
 

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