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Well, I have seen many comical acts where people balance a spoon (or a fork) on different parts of the face like on the tip of the nose, forehead etc.
The do this by blowing moist air (see below) and immediately putting it on the face

enter image description here

So i wanted to know is what is the force that temporarily binds the skin to the fork. I doubt it's friction or Van Der Walls force.
Can someone please clarify this for me? Is it some sort of chemical bond?

Some addition
Also another method of doing this was to rub the concave part of the spoon on the tip of the nose. This article states how to do it properly. In the 2nd point it states

Eventually you will feel a slight tendency for the spoon to resist on the downstroke.

What is this resisting tendency?

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My guess is that the effect is primarily due to suction - the fact that you apply a coat of water to the metal and then press on it can create a pseudo-vacuum. – CHM May 29 '12 at 22:00
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Sounds more physics to me.... – Canageek May 29 '12 at 22:06
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Why would you doubt it is friction? – Justin May 29 '12 at 23:14
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Thank you to all that have expressed concern about the on-topic nature of this question. We have discussed it and think that the forces at work are Van der Wals/adhesive forces/induced-dipole/etc interactions which makes it okay for Chem.SE. We understand that there is much overlap with Physics, but we have elected to retain the question. Opposing viewpoints are welcome, either on Meta or in chat. – jonsca♦ May 30 '12 at 3:12
Relevant chatroom discussion. Feel free to drop by and add your views! – ManishEarth♦ May 30 '12 at 9:15

1 Answer

up vote 2 down vote

I would say the answer on this website is pretty near perfect.

To summarize, you need 2 things:

  1. Enough friction between your nose and the spoon
  2. The center of mass of the spoon should be on a line vertically downwards THROUGH the tip of your nose as illustrated in this image from the same website:

enter image description here

The friction is highest if both your skin and the spoon are free of greasy `lubricants'. Breathing on the spoon will add more friction by depositing a very thin (only a few atomic layers) film of water which, on this scale, behaves solid-like due to ordering effects as shown in this paper.

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