Talk:1867: Physics Confession - Revision history

108.162.245.200: I'm dumb and didn't realize it was a joke and I was wrong anyway

2020-12-17T22:24:32Z

I'm dumb and didn't realize it was a joke and I was wrong anyway

108.162.245.200: Isn't -40C colder than -40F???; also, various grammar corrections.

2020-12-17T22:21:39Z

Isn't -40C colder than -40F???; also, various grammar corrections.

162.158.154.229 at 15:52, 9 January 2020

2020-01-09T15:52:23Z

162.158.154.229: Added a nice recent reference on ice skating

2020-01-09T15:50:42Z

Added a nice recent reference on ice skating

Dgbrt at 18:03, 1 August 2017

2017-08-01T18:03:04Z

162.158.114.16 at 11:27, 31 July 2017

2017-07-31T11:27:05Z

Davidgro at 23:55, 28 July 2017

2017-07-28T23:55:17Z

162.158.74.219 at 03:22, 28 July 2017

2017-07-28T03:22:24Z

141.101.98.244: Removed spam

2017-07-25T13:27:18Z

Removed spam

Lackadaisical: Undo revision 143146 by 108.162.245.238 (talk) Moving post to bottom, to maintain order of comments.

2017-07-24T17:59:38Z

Undo revision 143146 by 108.162.245.238 (talk) Moving post to bottom, to maintain order of comments.

@@ Line 17: / Line 17: @@
 "...ice skating stops being possible below around -30C".  Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades) {{unsigned ip|162.158.74.219}}
 : -40C? Ha! Try -40F! [[User:Davidgro|davidgro]] ([[User talk:Davidgro|talk]]) 23:55, 28 July 2017 (UTC)
 : Ice skating works because ice is slippery and skates reduce the surface touching the ice which reduces the friction increasing how slippery it is. However, it is a special case of the question: "Why is ice slippery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16|162.158.114.16]] 11:27, 31 July 2017 (UTC)
 A recent article discusses ice skating things [https://journals.aps.org/prx/abstract/10.1103/PhysRevX.9.041025 here]. Looks like the confined melted water film behaves oddly (viscoelastically) and unexpectedly gains ideal lubrication properties for skiing and skating. Surface hydrophobicity also affects sliding coefficients not by changing the thickness of melted films but rather the local water (complex) viscosity. However, they do not try this at -40 C (or -40 F as slyly pointed out above).

@@ Line 10: / Line 10: @@
 ;Explanation of skating
-A lot of people both here and on Reddit seem to be talking about pressure of the skates reducing the melting point. Pressure of the skates can only reduce the melting point by about 0.5C, so this is clearly not sufficient to produce a layer of liquid below -0.5C. The more correct explanation is that there is an ever-present layer of liquid on the surface of most crystals, including ice - this is the best explanation that exists right now, and explains why ice skating stops being possible below around -30C (and is hard at intermediate temperatures). This is the explanation offered by most modern university courses on thermodynamics or materials science - here is an excerpt from a University of Cambridge materials science course: [https://imgur.com/a/8bZxG Excerpt] [[User:Jaredjeya|Jaredjeya]] ([[User talk:Jaredjeya|talk]]) 13:03, 24 July 2017 (UTC)
+A lot of people both here and on Reddit seem to be talking about the pressure of the skates reducing the melting point. The pressure of the skates can only reduce the melting point by about 0.5C, so this is clearly not sufficient to produce a layer of liquid below -0.5C. The more correct explanation is that there is an ever-present layer of liquid on the surface of most crystals, including ice - this is the best explanation that exists right now and explains why ice skating stops being possible below around -30C (and is hard at intermediate temperatures). This is the explanation offered by most modern university courses on thermodynamics or materials science - here is an excerpt from a University of Cambridge materials science course: [https://imgur.com/a/8bZxG Excerpt] [[User:Jaredjeya|Jaredjeya]] ([[User talk:Jaredjeya|talk]]) 13:03, 24 July 2017 (UTC)
 : I've just looked at the article linked in the explanation, whoever put it in didn't read the full article because it goes on to mention exactly this explanation. [[User:Jaredjeya|Jaredjeya]] ([[User talk:Jaredjeya|talk]]) 13:07, 24 July 2017 (UTC)
@@ Line 17: / Line 17: @@
 "...ice skating stops being possible below around -30C".  Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades) {{unsigned ip|162.158.74.219}}
 : -40C? Ha! Try -40F! [[User:Davidgro|davidgro]] ([[User talk:Davidgro|talk]]) 23:55, 28 July 2017 (UTC)
-: Ice skating works because ice is slipery and skates reduces the surface touching the ice which reduces the friction increasing how slipery it is. However it is a special case of the question: "Why is ice slipery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16|162.158.114.16]] 11:27, 31 July 2017 (UTC)
+: Ice skating works because ice is slippery and skates reduce the surface touching the ice which reduces the friction increasing how slippery it is. However, it is a special case of the question: "Why is ice slippery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16|162.158.114.16]] 11:27, 31 July 2017 (UTC)
-A recent article discusses the ice skating things [https://journals.aps.org/prx/abstract/10.1103/PhysRevX.9.041025 here]. Looks like the confined melted water film behaves oddly (viscoelastically) and unexpectedly gains ideal lubrication properties for skiing and skating. Surface hydrophobicity also affects sliding coefficients not by changing the thickness of melted films but rather the local water (complex) viscosity. However they do not try this at -40 C (or -40 F as slyly pointed out above).
+A recent article discusses ice skating things [https://journals.aps.org/prx/abstract/10.1103/PhysRevX.9.041025 here]. Looks like the confined melted water film behaves oddly (viscoelastically) and unexpectedly gains ideal lubrication properties for skiing and skating. Surface hydrophobicity also affects sliding coefficients not by changing the thickness of melted films but rather the local water (complex) viscosity. However, they do not try this at -40 C (or -40 F as slyly pointed out above).

← Older revision		Revision as of 15:52, 9 January 2020
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	: Ice skating works because ice is slipery and skates reduces the surface touching the ice which reduces the friction increasing how slipery it is. However it is a special case of the question: "Why is ice slipery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16\|162.158.114.16]] 11:27, 31 July 2017 (UTC)		: Ice skating works because ice is slipery and skates reduces the surface touching the ice which reduces the friction increasing how slipery it is. However it is a special case of the question: "Why is ice slipery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16\|162.158.114.16]] 11:27, 31 July 2017 (UTC)

−	: A recent article discusses the ice skating things [https://journals.aps.org/prx/abstract/10.1103/PhysRevX.9.041025 here]. Looks like the confined melted water film behaves oddly (viscoelastically) and unexpectedly gains ideal lubrication properties for skiing and skating. Surface hydrophobicity also affects sliding coefficients not by changing the thickness of melted films but rather the local water (complex) viscosity. However they do not try this at -40 C (or -40 F as slyly pointed out above).	+	A recent article discusses the ice skating things [https://journals.aps.org/prx/abstract/10.1103/PhysRevX.9.041025 here]. Looks like the confined melted water film behaves oddly (viscoelastically) and unexpectedly gains ideal lubrication properties for skiing and skating. Surface hydrophobicity also affects sliding coefficients not by changing the thickness of melted films but rather the local water (complex) viscosity. However they do not try this at -40 C (or -40 F as slyly pointed out above).

← Older revision		Revision as of 15:50, 9 January 2020
Line 19:		Line 19:

	: Ice skating works because ice is slipery and skates reduces the surface touching the ice which reduces the friction increasing how slipery it is. However it is a special case of the question: "Why is ice slipery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16\|162.158.114.16]] 11:27, 31 July 2017 (UTC)		: Ice skating works because ice is slipery and skates reduces the surface touching the ice which reduces the friction increasing how slipery it is. However it is a special case of the question: "Why is ice slipery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16\|162.158.114.16]] 11:27, 31 July 2017 (UTC)
		+
		+	: A recent article discusses the ice skating things [https://journals.aps.org/prx/abstract/10.1103/PhysRevX.9.041025 here]. Looks like the confined melted water film behaves oddly (viscoelastically) and unexpectedly gains ideal lubrication properties for skiing and skating. Surface hydrophobicity also affects sliding coefficients not by changing the thickness of melted films but rather the local water (complex) viscosity. However they do not try this at -40 C (or -40 F as slyly pointed out above).

@@ Line 15: / Line 15: @@
 ::Good ol' circular reasoning. [[User:OldCorps|OldCorps]] ([[User talk:OldCorps|talk]]) 15:48, 24 July 2017 (UTC)
-"...ice skating stops being possible below around -30C".  Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades)
+"...ice skating stops being possible below around -30C".  Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades) {{unsigned ip|162.158.74.219}}
 : -40C? Ha! Try -40F! [[User:Davidgro|davidgro]] ([[User talk:Davidgro|talk]]) 23:55, 28 July 2017 (UTC)
 : Ice skating works because ice is slipery and skates reduces the surface touching the ice which reduces the friction increasing how slipery it is. However it is a special case of the question: "Why is ice slipery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16|162.158.114.16]] 11:27, 31 July 2017 (UTC)

← Older revision		Revision as of 11:27, 31 July 2017
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	"...ice skating stops being possible below around -30C". Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades)		"...ice skating stops being possible below around -30C". Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades)
	: -40C? Ha! Try -40F! [[User:Davidgro\|davidgro]] ([[User talk:Davidgro\|talk]]) 23:55, 28 July 2017 (UTC)		: -40C? Ha! Try -40F! [[User:Davidgro\|davidgro]] ([[User talk:Davidgro\|talk]]) 23:55, 28 July 2017 (UTC)
		+
		+	: Ice skating works because ice is slipery and skates reduces the surface touching the ice which reduces the friction increasing how slipery it is. However it is a special case of the question: "Why is ice slipery in the first place?" Which is not fully understood.[[Special:Contributions/162.158.114.16\|162.158.114.16]] 11:27, 31 July 2017 (UTC)

← Older revision		Revision as of 23:55, 28 July 2017
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	"...ice skating stops being possible below around -30C". Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades)		"...ice skating stops being possible below around -30C". Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades)
		+	: -40C? Ha! Try -40F! [[User:Davidgro\|davidgro]] ([[User talk:Davidgro\|talk]]) 23:55, 28 July 2017 (UTC)

← Older revision		Revision as of 03:22, 28 July 2017
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	: I've just looked at the article linked in the explanation, whoever put it in didn't read the full article because it goes on to mention exactly this explanation. [[User:Jaredjeya\|Jaredjeya]] ([[User talk:Jaredjeya\|talk]]) 13:07, 24 July 2017 (UTC)		: I've just looked at the article linked in the explanation, whoever put it in didn't read the full article because it goes on to mention exactly this explanation. [[User:Jaredjeya\|Jaredjeya]] ([[User talk:Jaredjeya\|talk]]) 13:07, 24 July 2017 (UTC)
	::Good ol' circular reasoning. [[User:OldCorps\|OldCorps]] ([[User talk:OldCorps\|talk]]) 15:48, 24 July 2017 (UTC)		::Good ol' circular reasoning. [[User:OldCorps\|OldCorps]] ([[User talk:OldCorps\|talk]]) 15:48, 24 July 2017 (UTC)
		+
		+	"...ice skating stops being possible below around -30C". Not true. I've skated at -40C. It's effing stupid, risk of frostbite in minutes, but still works. (Living North of 60 for 4+ decades)

← Older revision		Revision as of 13:27, 25 July 2017
Line 14:		Line 14:
	: I've just looked at the article linked in the explanation, whoever put it in didn't read the full article because it goes on to mention exactly this explanation. [[User:Jaredjeya\|Jaredjeya]] ([[User talk:Jaredjeya\|talk]]) 13:07, 24 July 2017 (UTC)		: I've just looked at the article linked in the explanation, whoever put it in didn't read the full article because it goes on to mention exactly this explanation. [[User:Jaredjeya\|Jaredjeya]] ([[User talk:Jaredjeya\|talk]]) 13:07, 24 July 2017 (UTC)
	::Good ol' circular reasoning. [[User:OldCorps\|OldCorps]] ([[User talk:OldCorps\|talk]]) 15:48, 24 July 2017 (UTC)		::Good ol' circular reasoning. [[User:OldCorps\|OldCorps]] ([[User talk:OldCorps\|talk]]) 15:48, 24 July 2017 (UTC)
−
−	~~F1RST P0ST!!!!!~~

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 <!--Please sign your posts with ~~~~ and not delete this comment.-->
 F1rst P0st http://www.explainxkcd.com/wiki/index.php/269:_TCMP [[Special:Contributions/172.68.141.190|172.68.141.190]] 07:54, 24 July 2017 (UTC)
@@ Line 16: / Line 14: @@
 : I've just looked at the article linked in the explanation, whoever put it in didn't read the full article because it goes on to mention exactly this explanation. [[User:Jaredjeya|Jaredjeya]] ([[User talk:Jaredjeya|talk]]) 13:07, 24 July 2017 (UTC)
 ::Good ol' circular reasoning. [[User:OldCorps|OldCorps]] ([[User talk:OldCorps|talk]]) 15:48, 24 July 2017 (UTC)