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Assume there is a completely frictionless surface. Would touching such a surface be possible? If so, what would it feel to the touch?

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Guys, if you vote down this question, I'd appreciate it if you told me why. I'm pretty sure this is the place to ask this question... – Omer van Kloeten Jun 17 '12 at 7:55
Yes, touching is possible, but I am not sure how it will feel. Physicists are mostly concerned with "what will happen" and not "how would it feel". – leongz Jun 17 '12 at 8:08
I'm well aware that my question goes into the realm of physiology, but since I've seen several questions on Touch here I think this is the place. – Omer van Kloeten Jun 17 '12 at 8:59
While I didn't downvote, I don't think thiis is a Physics questions, more like neourology, because it is about what you feel. – Dimensio1n0 Jul 16 '13 at 4:37
""more like neourology, because it is about what you feel."" This is nonsense, because then every observation is neurology. Even a pointer of an instrument is read via your eyes nerves. – Georg Jul 16 '13 at 11:17

2 Answers 2

up vote 8 down vote accepted

I'd guess the downvote (the downvote wasn't me BTW :-) is because "what your fingers feel" isn't really a physics question. I'd say it was biology or physiology or something like that.

Anyhow, to get back to your question, it's possible to make surfaces that are almost entirely frictionless by using a fluid layer as a lubricant. For example if you spread a thin layer of dimethicone on glass and rub your finger on it there is almost no resistance. Alternatively you can use a metal surface with tiny holes in it and pump air through the holes. Again when you rub your finger on the surface there is almost no friction. In both cases it's because a thin layer of fluid (oil in the first case and air in the second) prevents your finger from actually touching the surface.

As to what it feels like, well I have personal experience of both, and it just feels slippery; a bit like touching ice but without the sensation of cold. It's really nothing special - sorry!

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Having some lubricant oil on any surface would be enough. The difference to "total" frictionless is small then. BTW silanized glass is not very slippery! – Georg Jul 16 '13 at 9:20

I think that frictionless surface can't be felt.

I'll give you an example.

When you are walking, you feel air.

When you are running you feel it better.

And when travelling by any motor vehicle, you feel it in much better way.

This shows that friction is important to feel.

Thats why you can't feel frictionless surface.

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So it doesn't hurt when you smack your thumb with a frictionless hammer? That would be an interesting product. – Jens Schauder Jul 16 '13 at 11:12
So that means if you push your finger vertically onto a frictionless table you won't feel the force applied by the table onto you? Sure, the moment your force has a horizontal component, it will slip, but that doesn't mean you can't feel surfaces without friction. – mikhailcazi Jul 16 '13 at 12:29
Another thing. When you are stationary inside water, can't you feel it all around you? You do not need to locomote inside the water to feel it! You are just used to all the air about you, which makes you think you can't 'feel' it. If you ever experience vacuum on your skin, you'll know how it is to not feel any surface on your skin. :) – mikhailcazi Jul 16 '13 at 12:31

protected by Qmechanic Jul 7 '13 at 14:49

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