Talk:Stiction

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I think the main Problem with this "disambiguation" page is that it is no real disambiguation, since, as far as my understanding goes, all three subpages describe the same physical effect.--Deelkar (talk) 02:59, 4 May 2005 (UTC)

The word "portmanteau" is misspelled on the stiction page. 70.168.77.2 21:46, 27 July 2007 (UTC)duanefromri, 27 July 2007

Perhaps an additional reference to wet or dry etching could help, as the dry etchant xenon difluoride displays the characteristic of much less stiction? Xenon difluoride etches better. Ideally, there would be pictures showing the products of two different etchants, one with stiction and one without? The use of the word "stiction" in this context seems very different. —Preceding unsigned comment added by 67.150.169.84 (talk) 19:31, 9 January 2008 (UTC)

I just wanted to say that I was very glad to find this page. I was having a discussion about the phenomenon of stiction which was common with hard drives and led to failure... and a search led me here. I was once again grateful to wikipedia for answering a question I could not find an answer to elsewhere--207.182.34.36 (talk) 05:24, 15 January 2008 (UTC)

[edit] minor editing and some correction

Modified the paragraph regarding hard disk stiction to reflect current views. —Preceding unsigned comment added by Pdinhofer (talk • contribs) 16:53, 11 January 2008 (UTC)

[edit] Definition

This article seems to be vague about the definition. On the one hand it sounds like it's just talking about good old static friction, which is usually lower than kinetic friction; on the other hand, it sounds like it's talking about surface bonding. What's this really about? —Ben FrantzDale (talk) 04:23, 2 April 2008 (UTC)

[edit] Faulty experiment

The experiment at the top of the page is faulty, because of course the piece of wood is not moving at a steady speed, but at an accelerating rate, so in order for it to stop, it wouldn't merely have to resist the movement by friction, but would have to also with that friction be able to counteract the already accumulated impetus. I am not sure if I am explaining this at all coherently, but in any case it is clear to me the experiment doesn't demonstrate what it purports to demonstrate. -- Cimon Avaro; on a pogostick. (talk) 15:33, 14 April 2008 (UTC)

I don't like this article overall, but that example seems to be a valid experiment to show that kinetic friction is lower than static friction. This "impetus" (inertia) that you describe is, I think, part of the reason that kinetic friction is lower, but the example assumes small initial bump to get it moving; presumably that could be an arbitrarily small initial velocity. —Ben FrantzDale (talk) 00:19, 15 April 2008 (UTC)
It could be arbitrarily small only in theory, and experiments aren't about "in theory" but about "in practise". So that makes it a poor real experiment. In practise, what is what experiments are about, there will be a noticable overshoot of the necessary initial velocity, and after that acceleration will take over, with no return in sight. I wonder If what I say is more understandable if I phrase it like that. -- Cimon Avaro; on a pogostick. (talk) 01:32, 15 April 2008 (UTC)
Yes and no. In practice you could probably give the block an initial velocity of well less than 1mm/sec and have it still keep going. At some point the assumptions of Coulomb friction will break down, though, so you'll need a better model of physics. For example, if the elasticity of the block becomes significant, then moving the top of the block at velocity v could mean that the bottom of the block is still stopped. If you then let go of the top, it would recoil (albeit not very far :-) ). I suspect that for most common materials, this elasticity is the first thing that makes this experiment break down; as long as the contact surface of the part is moving as a rigid body, it should all break static friction all at once. There is, of course, an end to the acceleration which is the terminal velocity. The real proof is in the pudding, though. Give it a try: Take a surface you can tip and a small rigid thing that sits flat on it. Tip the surface until the thing starts to slide. Then tip the surface back down a bit. Put the thing back on the surface and see if you can nudge it slow enough so that it moves but doesn't take off on its own. I just tried it with a small jar on a wooden box and couldn't push the jar slowly enough for it to not start sliding on its own. —Ben FrantzDale (talk) 02:21, 16 April 2008 (UTC)
That may be so, I still think "experiment" may not be the best word for it. Perhaps "demonstration", since it does indeed illustrate the fact to the layman, but fails to be rigorous in the scientific sense, so as to be a valid experiment. Would it be okay to you if we substituted the word "demonstration" for "experiment"? -- Cimon Avaro; on a pogostick. (talk) 06:02, 20 April 2008 (UTC)