Difference between revisions of "697: Tensile vs. Shear Strength"

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Revision as of 23:41, 22 May 2014

Tensile vs. Shear Strength
Although really, the damage was done when the party planners took the hole punch to the elevator ribbon to hang up the sign.
Title text: Although really, the damage was done when the party planners took the hole punch to the elevator ribbon to hang up the sign.


Tensile strength represents how hard you can pull on something without it breaking. Shear strength represents how hard you can try to cut it without it breaking. Many materials have great tensile strength but low shear strength (such as dental floss — try to break it by just pulling on two ends), including whatever this space elevator is made of. It can hold the elevator in place, with one end on the ground and one in space, but it can be cut with a simple pair of pruning shears (also a pun on shear strength).

The title text makes the point that even before Black Hat cut the space elevator's cable in two, it was ruined by the holes in it for the banner. The holes would reduce the surface area of the cross section of the pole, dwarfing its ability to keep the elevator attached to the ground.


[A banner flutters in the breeze, evidently attached to the elevator it mentions in its text. It reads "SPACE ELEVATOR" "GRAND OPENING".]
[A space elevator occupies the height of the frame, consisting of a base, a ribbon extending out into space, and an elevator unit with standard elevator features such as sliding doors and up/down buttons.]
[The following lines appear split across the elevator itself, the rhyming portions of the text separated from the others.]
          After countless    engineers
     Spend trillions over    fifty years,
           A modern babel    disappears
Because some fuck brought    pruning shears
[Five individuals stand at the base of the elevator: Megan, Cueball, Ponytail who has recently opened a bottle of champagne, an alarmed man, and Black Hat, who has smuggled the aforementioned shears into the ceremony and unceremoniously turned it into a ribbon cutting.]

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Does anyone know the tensile vs. shear strength of nanotubes? Djbrasier ([[User talk:Djbrasier|talk]]) 20:33, 3 September 2013 (UTC)

"but it can be cut with a simple pair of pruning shears (also a pun on shear strength)" - I don't know the precise etymology of the word shears, but I would assume they are called such precisely because they operate on a shearing principle. While it is fair to assume that the use of the words 'pruning shears' is intentional (rather than 'scissors' or similar) , I wouldn't call it a pun (exploiting multiple meanings of words). --Pudder (talk) 16:07, 11 September 2014 (UTC) (Retroactively signed)

I agree, it's not a pun. I'm going to change that. Spiral phi (talk) 19:32, 27 August 2014 (UTC)

I can't immediately think of any other rhyming comics. Are there any others? --Pudder (talk) 16:07, 11 September 2014 (UTC)

At least 206: Reno Rhymes, 491: Twitter and 805: Paradise City, and probably others. Pelosujamo (talk) 17:32, 23 September 2014 (UTC)

Though the thing would have buckled before all this could even have a chance to happen 16:22, 11 October 2014 (UTC)

Buckling is specifically a failure under compressive load. I'm assuming we are looking at a cable under tensile load caused by centrifugal force. (The old swinging a bucket on a rope trick). Wikipedia has an interesting Space Elevator article. --Pudder (talk) 12:23, 12 December 2014 (UTC)

Aargh! The first line lacks a syllable... E.g. THEN after countless engineers...Mumiemonstret (talk) 10:31, 17 October 2014 (UTC)

I'm pretty sure the 3rd line's been changed; when I first read it, it ended with either "turns to tears" or "ends in tears". Can anyone confirm? Promethean (talk) 19:03, 31 May 2015 (UTC)

More accurate to refer to punched holes in terms of being stress concentrators than in terms of cross-section reduction. Sharp corners can reduce stress to failure massively while only marginally reducing cross-sectional area 16:09, 24 December 2015 (UTC)

In reality, I believe that any space elevator would be nearly perfectly balanced, to the point that it would not even need to necessarily be connected to the ground. That is of course why a space elevator in and of itself is possible and why a material with great tensile strength is needed, as it would be perfectly balanced. (talk) (please sign your comments with ~~~~)

I'm pretty sure you guys missed the reference to Burma Shave. The setup of the text is identical to the "burma shave" campaign (4 rhyming lines + "Burma Shave"). In this case Pruning Shears is used instead of Burma Shave which sounds quite similar (this is why he choose that over "scissors" or similar). See comic 491 for another reference. 15:11, 24 August 2016 (UTC) msx80

The Burma Shave connection is weak. The signs used only three or four syllables per line and just one rhyme (e.g., "Ben met Anna / Made a hit / Neglected beard / Ben Anna split"), and the "Burma Shave" was on a fifth, separate sign, not part of the rhyme. Gmcgath (talk) 20:23, 25 October 2016 (UTC)