Talk:Rope trick effect

message: Here is a coloured version of the image. I'm not sure if its worth swapping it with the present image.--Trounce 14:21, 28 July 2006 (UTC)
replies: text: I would have to say that no it is not woth it. does it look neat? sure but what new information does adding red to the image convey to the reader? none I think and it even may convey an incorrect impression that this was the actual color of the thing which would not be good. --Deglr6328 00:02, 29 July 2006 (UTC)
thread_title: Colored version of image?

message: Exactly what ropes are burning? and what is a "shot cab"?
:Mooring ropes from the shot cab to the ground, like those you can see on radio masts and other tall towers.  The shot cab is the housing at the top of the tower that contains the explosive device. Waerloeg 21:20, 26 August 2006 (UTC)
replies: text: It would be nice for experts to change the article to say so. I've done it using the information above. Bazza 12:24, 27 March 2007 (UTC)
thread_title:  Confused... 

message: The text says that "The "rope tricks" which protrude from the bottom of the fireball are caused by the heating, rapid vaporization and then expansion of mooring cables.... induced by exposure to high-intensity visible light radiation, which causes the effect."
Since light radiation travels at essentially infinite velocity relative to the fireball shockwave, one would expect vaporization of the mooring cables along their entire length, though perhaps with slightly decreasing vigour, as you go radially outward.
This is clearly not the case -- the "rope tricks" show a definite start, with no sign at all of any heating farther out, radially (besides being brighter than the fireball, as noted in a previous discussion).
Moreover, the form of the "rope tricks" is conical, radially inward from the start, which is characteristic of a shock rarefaction wave, following behind the lead shock in the wire itself (shocks travel faster in dense media like the steel wires, which is why the spikes stick out ahead of the fireball).
The cited description of tests by Malik contradict this, but this was taken out of a text describing different experiments, where the wires were not mooring cables for the bomb tower itself, but rather cables going parallel to the tower, at some distance away.
In such an arrangement the wires get broadsided by the light flux, and of course vaporize along their entire length at once, as expected.
By contrast, wires going radially away from the bomb will not see much light, because the light is also going out radially (ie. parallel to the wires, not perpendicular).
-- Jaro 02:11, 30 March 2007 (UTC)
replies: text: Your thoughts are intriguing and seem plausible. Can you cite some references?--Deglr6328 12:33, 31 March 2007 (UTC)

text: The description above was exactly my thoughts upon seeing the pictures for the first time.  The light / xray / gamma radiation flux would be roughly isotropic along the entire cable length due to the (as noted above) essentially infinite speed of light.  I believe what we are primarily seeing is shock waves in the cables outpacing the atmospheric shock wave / fireball.  The often cited explanation never made sense to me.  MrKeg 11 January, 2018  — Preceding unsigned comment added by 205.156.84.229 (talk) 22:27, 11 January 2018 (UTC)
thread_title:  "rope tricks" description incorrect, mixed up with other experiments 

message: Instead of having an edit war let's talk about this here.  The WP style guide is clear that the singular K is to be used for Kelvin.  Is there some good reason not to follow the style guide?  Brianhe 23:56, 13 September 2007 (UTC)
thread_title:  Kelvin vs Kelvins 

message: I think I found the original document that a lot of the text in this article was cut and pasted from. I credited it at the bottom of the article. Take a look and see what you think, and monkey with the refs as necessary (I suck at that). --Milkbreath (talk) 00:15, 23 November 2007 (UTC)
thread_title:  Credit 

message: It might be worth mentioning in the article the 5 vertical white lines visible in the lower right corner of the picture are not an example of the rope trick effect. Smoke devices were ignited prior to the detonation of the nuclear device to better facilitate the measuring and charting the expansion and effect of the primary nuclear device.--Legomancer (talk) 03:03, 17 July 2008 (UTC)
replies: text: Indeed.  Neither though are they smoke at all, zoom in and you will see that.  They are actually 'blast line poles' - see the youtube video at about the time referenced www.youtube.com/watch?v=g0r_4v2hA5c?t=1210, I have amended the article and explained that. 51.6.235.3 (talk) 23:45, 11 November 2021 (UTC)
thread_title:  Additional info for Pic 

message: Not really part of the discussion, but has anyone else had trouble with the video clip? I clicked it and it flickered and went dead. A few times. When I tried the 'still shot' option, it froze my browser (Firefox 2) leaving me only able to shut windows. Closing and restarting Firefox didn't work until I closed it in Task Manager. 
By the way, I prefer the coloured image for the still - so long as it is clearly labelled as additionally coloured. It looks clearer to me. I'm slightly (you never know why the military do some things) puzzled as to why they would use rope rather than metal cable for anchorage. Did they not worry that it might fall over post-bang, or would metal cable vapourise just the same? Peridon (talk) 16:43, 15 September 2008 (UTC)
replies: text: The guy wires, and, indeed, the entire shot tower, were normally vaporized completely by the weapon fireball in a matter of milliseconds, so the construction of the guy wires didn't matter very much post-firing.  Even if a bomb didn't completely destroy its shot tower (as happened in only two US cases, the Buster Able fizzle and the Upshot-Knothole Ruth design failure), the tower would be heavily damaged by the high explosive trigger used (as seen in this photo of the Ruth shot tower) and therefore wouldn't be reused, so there was no reason to worry about their long-term stability; all they needed to be able to do was stay standing for the week or so that it would take to install the diagnostic equipment and the weapon itself in the shot cab before the test.  Indeed, some of the shot towers (including the one used in the famous Trinity shot) were of wooden construction!  Rdfox 76 (talk) 22:57, 15 September 2008 (UTC)
thread_title: Video problem

message: Can someone verify this number?  It seems extremely low.  Working with solar furnaces, only a 100X concentration would take quite a while to MELT metal, let alone instantly vaporize it.  With the inverse square law, plus the extremely brief duration of the thermal pulse, I would expect concentrations in terms of thousands or even millions of solar units.  From anecdotal evidence stating that at 10 miles the heat was roughly equivalent to full sunlight, and using a nominal distance of 100 feet for the limit of the "rope effect"  (more or less) a rough calculation would give a value on the order of about 280000 solar units.
Going back to the original quoted source, the original said "intensity over 100 times greater than the sun", note "sun" not "sunlight".  From the original author's reference to "the surface of the sun", just preceding this quote, implies that "sun" refers to the sun's surface.  The word "sunlight" is universally taken to be the intensity at the Earth's surface (not the surface of the sun) when used casually as a unit of intensity.  If anyone disagrees with this, please feel free to comment.  I have changed the text to read "surface of the Sun" in the meantime.  —Preceding unsigned comment added by Pmarshal (talk • contribs) 06:55, 5 April 2010 (UTC)
thread_title: "100 times the intensity of sunlight" seems like a gross underestimation

message: One of the outcomes never mentioned anywhere is that this gave them valuable information that eventually helped them configure the shape and placement of the "Secondary" used in thermonuclear (TN) weapons.Atomicjohn (talk) 22:39, 6 August 2011 (UTC)
thread_title:  Rope Trick experiments 

message: The paragraph starting with "The cause of the surface mottling is more complex..." isn't related to the title of the article, and, while super interesting, probably should get its own article.  Or so sayeth I, in my humble wikipedia lurker opinion. DGGenuine (talk) 06:56, 3 November 2011 (UTC)
thread_title:  Separate Article for Surface Mottling 

message: Without being able to prove it, my suspicion (after having discussed with a colleague) is that another effect may have a much greater impact. First of all, the effect seems to be most pronounced for structures (like mooring ropes) pointing radially away from the explosion center. There are Rapatronic movies like these], especially at 22 seconds video time, where you can see other metal structures (like the frame of the tower itself) which are not showing this effect at all. Not even the ground, which is exposed face-on to the radiation, shows similarly spectacular effects. Then, it has already been mentioned that Dr. Malik's experiments used non-radial test ropes rather then the mooring itself, so his conclusions are not necessarily valid for the latter.
Our explanation is that high-energy radiation (X-rays, gamma rays etc.) displace electrons (and thus electric charge) in the surrounding materials radially away from the center. In electrically conducting materials like steel ropes this displacement will cause massive electric currents, which may (at least partially) vaporize the ropes close to the fireball. The expansion of the spikes with time may simply be due to the quicker reaction a higher energy levels (same explanation as in the thermal radiation model). Metal structures face-on or at an angle to towards the nuclear device would not suffer from such strong currents since the electron displacement would be only along little more than its thickness, while electrons in radially positioned cables would be displaced along a long distance without leaving the cable. Of course, a lot of electrons is also displaced in the air, which is the main source of the electromagnetic pulse.
Why does Dr. Malik provide another, simpler (but thermodynamically not feasible) explanation? We don't know, but maybe he had been forced to provide a simple understandable, but wrong explanation, to obscure the correct mechanism for security reasons. The effect I described may be similar to that in a proposed X-ray laser device, which came into discussion e.g. for the SDI project in the 1980's. So, it is easily understandable, and not a vague conspiracy theory, that military secrecy issues required a misleading but convincing (at least to laypersons) explanation for this effect, which itself cannot be hidden.
It's a pity that Wikipedia does not allow original research even if it is clearly labeled as such, and neutral third-party research is not available. But maybe someone out there has already published a similar explanation and is simply not yet cited here.--SiriusB (talk) 13:31, 18 April 2012 (UTC)
thread_title:  Another possible explanation for the effect 

message: Some info looks plagiarized from http://nuclearweaponarchive.org/Usa/Tests/Tumblers.html  — Preceding unsigned comment added by Test35965 (talk • contribs) 22:20, 19 October 2012 (UTC)
replies: text: ...and is all cited as coming from there.  rdfox 76 (talk) 01:04, 20 October 2012 (UTC)
thread_title:  plagiarism 

message: VERY interesting article. However, the text makes several references to "the photo," "the photo above," etc. It is unclear (to me, at least) which photos are being referenced, especially given that the photos are all displayed to the side of the text, rather than above. PurpleChez (talk) 19:12, 5 August 2020 (UTC)
thread_title:  which photos