Is Black Widow Silk Stronger Than Steel?

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The Action Lab

The Action Lab

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@MoonGlow22
@MoonGlow22 Ай бұрын
2:34 "Now I have one single strand of black widow silk" You also have a black widow running free in your house...
@TsczhabyCC
@TsczhabyCC Ай бұрын
Worth
@_Protato
@_Protato Ай бұрын
*Sweating intensifies*
@matthews2243
@matthews2243 Ай бұрын
They're pretty common in certain areas. I'd just have to turn over a few flagstones here and I'd find some
@westonding8953
@westonding8953 Ай бұрын
@@TsczhabyCCno. Get the venom and study that too.
@redryder3721
@redryder3721 Ай бұрын
​@@matthews2243 If you don't mind me asking, what country is this? Just so that I can avoid it for the rest of my life...
@yat8347
@yat8347 Ай бұрын
Hi James! As others have mentioned, you did your first ultimate tensile strength calculation wrong -- you need to take into account the angles of the two threads. I measured a screenshot taken right before failure and found the thread on the left was 30deg. from horizontal and the thread on the right was 24deg. from horizontal. I'm a physics/math teacher and have a degree in mechanical engineering so I had some fun re-doing the calculations. The actual ultimate tensile strength is 1.37GPa -- better than you thought! Let me know if you'd like a link to the PDF. (I don't think I can post a dropbox link here.) :) IMO the biggest sources of error is your diameter measurement -- it doesn't look like you had very high resolution in the microscope capture, and there's always a possibility that the thread had a weaker/thinner spot somewhere you didn't look. Also note that for the pulling-up-from-jar method, any tiny spikes in tension force due to slight shakiness of your hand will not be picked up by the reading on the scale, due to the inertia of the heavy glass jar and scale bed. If you want to try the pulling-up-from-jar method again for a more accurate result, I would recommend using the duct tape to attach the silk to a stretchy material like a strand of spandex from old underwear/socks, to absorb shocks and allow you to turn translational motion with your hand into a slow, steady force increase.
@christianheichel
@christianheichel Ай бұрын
James! You should see this! Great stuff
@TenorSine
@TenorSine Ай бұрын
I was just about to say this. The setup immediately reminded me of a particular problem from my AP Physics class of a few years ago.
@alexwood9941
@alexwood9941 Ай бұрын
What a beautiful KZbin comment
@1.4142
@1.4142 Ай бұрын
Yeah, he probably assumed both to be 30º so mg=2*Fty=2*1/2 Ft=Ft But the angle of the camera is looking down so the angles are bigger than they look.
@cristinelcostachescu9585
@cristinelcostachescu9585 Ай бұрын
I would recommend him staying the hell away from a black widow... just saying...
@Ryan-ff2db
@Ryan-ff2db Ай бұрын
I am a Masonry Contractor that often stores blocks and bricks in my yard. They are essentially apartment complexes for Black Widows. You can tell a Black Widows home just from their webs as many strands together are incredibly strong and sticky(for a web). I've also been bitten twice that I know of. The bite isn't nearly as painful as a scorpion or bee sting but afterwards you will feel sick, like the flu. Cold chills and just a gross feeling. I was bit on the finger once and my forearm and shoulder had uncomfortable muscle spasms. Not severe but also not pleasant. Unless you're allergic to the venom, It's not a life threatening thing but I wouldn't recommend it.
@domvasta
@domvasta Ай бұрын
Yeah, I've been bitten by a redback, a close cousin, Latrodectus hasselti, it was a dry bite, so I was fine, but it was scary.
@Ryan-ff2db
@Ryan-ff2db Ай бұрын
@@domvasta Yeah, the Redback and Black Widow have similar venom although its believed the Redback may be a little more toxic. Nature seems to love venomous things down under as you guys have the most venomous spiders, snakes and aquatics in the world.
@minerscale
@minerscale Ай бұрын
here in Australia our most deadly spider will just kill you, and they're fucken' everywhere. Found a Sydney funnel web in a drawer on multiple separate occasions.
@Ryan-ff2db
@Ryan-ff2db Ай бұрын
@@minerscale Fortunately Funnel bites are very rare and there is antivenom. It also depends on where you are bit. You should have time to seek medical help if bit on the finger or arm/leg. However, if bit on the neck or torso you could be in a lot of trouble as death can happen in as little 15 minutes. I used to work with an Aussie and he said a funnel or Red Top are everywhere, pretty much under every rock. He also said never throw clothing or blankets on the ground as they will hide in them.
@joestitz239
@joestitz239 Ай бұрын
No serum to make Things subside ? Won't it affect kidneys getting filtered ? Or make nails yellow from overwhelmed immune system-excessive dead white cells ?
@amosbackstrom5366
@amosbackstrom5366 Ай бұрын
The craziest thing is, they didn't develop a unique new polymer to achieve these incredible strengths. The use amino acids, just like most other biological structures. They're just tangled up and cemented together in an incredibly complex way, so nearly every available bonding site is fully utilized.
@thegrimreader7981
@thegrimreader7981 Ай бұрын
Meaning we can theoretically synthesise these in labs
@homerodysseus4203
@homerodysseus4203 Ай бұрын
It really is a natural marvel of organic materials science
@carl8703
@carl8703 Ай бұрын
@@thegrimreader7981 Also: what other materials lie in wait for us somewhere in all the possible arrangements of atoms?
@sadrien
@sadrien Ай бұрын
@@thegrimreader7981 just think about how strong other biological structures can get with some highly advanced gene editing.
@bort6414
@bort6414 Ай бұрын
@@thegrimreader7981 It would be pointless, since high-performance metamaterials already exhibit significantly stronger properties than spider silk. High grades of kevlar approach 5GPas of tensile, some carbon fibers approach 300GPas. It is true that spider silk is remarkable for how a living being is able to produce it organically, but it does not mean it performs better.
@peniku8
@peniku8 Ай бұрын
WHERE IS THE SPIDER NOW
@Cluvr
@Cluvr Ай бұрын
Under your bed
@lucasvillani5484
@lucasvillani5484 Ай бұрын
Check your ears
@orionspur
@orionspur Ай бұрын
Under your toilet seat.
@linkinparker896
@linkinparker896 Ай бұрын
in your head in your head zombie zombie zombie zombie
@kdot8340
@kdot8340 Ай бұрын
Who cares
@Salinated
@Salinated Ай бұрын
As someone from Texas, Black widows are actually sorta chill. Not so chill I'd invite them to my house for coffee, but they aren't bothering me either
@JeffBilkins
@JeffBilkins Ай бұрын
spiders are welcome as long as they stay in the upper half of the room
@Anas-1220
@Anas-1220 Ай бұрын
​@@JeffBilkinsNO NOOOO I AM NOT LETTING THEM JUMP ON ME WHILE I'M SLEEPING... OR DOING ANYTHING!!!!
@homerodysseus4203
@homerodysseus4203 Ай бұрын
​​@@Anas-1220spiders don't want to be near you either, but from my observations in life they may share a mutualistic symbiotic relationship with humans where they gain food from the insects we consider pests.
@chir0pter
@chir0pter Ай бұрын
When I first moved to black widow country, I found one behind my toilet. I thought it was cool so I left it there and even tried to feed it a moth, which bounced off the web and flew away. Apparently this frustrated the spider and it determined its web needed improvement, because the next day I opened my bathroom door and walked right into a black widow web spanning floor to ceiling. I saw the spider retreating up a dragline out of the corner of my eye. Needless to say that was the end of the pet free ranging black widow experiment
@McZambie1203
@McZambie1203 Ай бұрын
I had a male one just chilling in the corner of my room for a while, he caught mosquitoes and stuff so I was chill with him
@LogiDMA
@LogiDMA Ай бұрын
"deadliest spider in the US" *continues to poke it*
@spoopyd.8910
@spoopyd.8910 Ай бұрын
Unless you're a kid, or your immune system is compromised, you'll be fine even if it bites you. It'll just hurt a lot.
@LastGoatKnight
@LastGoatKnight Ай бұрын
They're chill until you don't provoke them. Every venomous animal uses their venom for hunting, not for defense so they usually warn you before they attack. The ususal method you need to follow when handling animals of this kind: don't pester them, let them move freely, don't make suddden moves or sounds That's it, you can handle any animal like the black widow. They won't hurt you if you doesn't seem like a threat to them and even if you do, they rather run away from you than actually attack
@spoopyd.8910
@spoopyd.8910 Ай бұрын
@@LastGoatKnight Please don't handle animals even with this method. Just leave them alone.
@BlakeEM
@BlakeEM Ай бұрын
​​@@spoopyd.8910 Why not? Our exterminator handled them and said the same thing. They only bite if provoked. People are usually bitten after reaching into them and startling them. I wouldn't play with them if you're allergic, but they're relatively safe otherwise.
@spoopyd.8910
@spoopyd.8910 Ай бұрын
@@BlakeEM A grenade wouldn't blow up unless you remove the pin. But that doesn't mean you should fondle them like your balls. Just don't play the stupid games so you never win the stupid prizes. Is that so hard to understand?
@NinjaNezumi
@NinjaNezumi Ай бұрын
I love how you just let the widow walk off. DUDE - CAPTURE THE WIDOW!
@nathanvanblommestein4316
@nathanvanblommestein4316 Ай бұрын
Nah it chill. Redbacks can be found in ٪98 of homes in Australia and only about 200 people died from them last year. More likely to die in a car crash
@arcadeunskilled
@arcadeunskilled Ай бұрын
@@nathanvanblommestein4316 Did you mean got bitten? Because there haven't been any deaths at all since 2016, when one (1) person did die from a secondary infection after a bite, but 200some is the estimated amount of annual bites requiring medical attention.
@Sotanaht01
@Sotanaht01 Ай бұрын
@@nathanvanblommestein4316 Just because it probably won't kill you, doesn't mean it won't make you wish you were dead.
@tjakal
@tjakal Ай бұрын
Do you even understand the how the word 'Action' goes infront of 'Lab' ? A Black Widow roaming about is completely inline with the spirit of this channel.
@Fahrenheit4051
@Fahrenheit4051 Ай бұрын
@@nathanvanblommestein4316 200 people did not die from redback spider bites last year. The correct number? Zero. They are dangerous, but not cobra or funnel web spider dangerous.
@GigaCraft-420
@GigaCraft-420 Ай бұрын
Next video be like: My friend found a crocodile in his backyard, and I'm going to test if it really has the strongest bite
@pdarivemula
@pdarivemula Ай бұрын
Chat is this real?
@RandomBogey
@RandomBogey Ай бұрын
The first time I ever encountered a black widow, I was 13 helping a family friend prepare to expand his garage and I had to relocate a stack of lumber (I wasn’t aware at the time, but stacks of wood are a common hiding place for black widows outside) that was raised off the ground by cinder blocks, so the blocks were the last things to move and without a thought, I stuck my bare hand in the hollow part of a cinder block, that had been under a stack of lumber for who knows how long, to pick it up. As I was carrying it, a black widow climbed onto the top of the block from the other side of the same hole I had my bare hand in and made its way across the top back towards my hand. I dropped the block, then crouched to get a better look at it and almost couldn’t believe it was even a real spider. It was pitch black and so shiny, like the blackest black mirror finish paint, and the red hourglass outline was so sharp and such a bright vivid contrasting red that it looked like a toy or something. I captured it and brought it home with me, but my mom was furious and made me kill it, so I preserved it in rubbing alcohol in a glass baby food jar that’s still in a drawer at my parents house 20-something years later
@CommonG
@CommonG 27 күн бұрын
dam bro u aint have to kill it 😭
@JoshuaNagel536
@JoshuaNagel536 22 күн бұрын
My first encounter with one was probably when I was 4 or something
@ryanclemons1
@ryanclemons1 17 күн бұрын
@@CommonG you do if your mom says to kill it.
@enox3547
@enox3547 Ай бұрын
Sets world’s brightest flashlight down, without turning it off. I was half expecting the desk to burst into flames
@homerodysseus4203
@homerodysseus4203 Ай бұрын
Yeah, or at the very least end up with some burnt out diodes
@SpydersByte
@SpydersByte Ай бұрын
@@homerodysseus4203 lol yea my thought as well, he already proved he can burn them out by setting it against a mirror for a few seconds
@assoztube
@assoztube Ай бұрын
Whats wrong Christian Boy
@gistasbanaitis473
@gistasbanaitis473 Ай бұрын
I actually half expected the light to push on the scales
@TheActionLab
@TheActionLab Ай бұрын
I only had it set at 1,000 lumen:)
@driverjamescopeland
@driverjamescopeland Ай бұрын
Most spiders, particularly black widows, produce several types of silk. It's hard to harvest the best quality silk from spiders, because the strongest variant is reserved for restraining prey once caught... it's even stronger than anchor silk used for their webs.
@MengusDew
@MengusDew Ай бұрын
IS it differnt TYPES, though? Or, is it just the same material layered differently? Semantics, I know, but my question is genuine, not condescending. I am curious.
@ontopoftheroof
@ontopoftheroof Ай бұрын
"...when the females are really hungry." Well, that will surely put Mr. Widow at ease.
@DucatiKozak
@DucatiKozak Ай бұрын
That's why Mr. Widow ALWAYS buys dinner before seducing Ms. Widow! A good rule of thumb for all of us!
@nerdnam
@nerdnam Ай бұрын
They'll want to bring a box of chocolate.
@FrankApelledalph
@FrankApelledalph Ай бұрын
That's why Black Widow was a very sassy and petty bitch, when she was first introduced in the marvel movies. She was just hungry.
@jaredragland4707
@jaredragland4707 Ай бұрын
The one that lived in my garage had five generations of offspring, and I saw at least three (might have been four) ex husbands desiccating in that big web. Might have been a conducive environment for spousal cannibalism, or maybe she was just mean, but the odds were not with the males.
@randyj4452
@randyj4452 Ай бұрын
My uncle raised Black Widows in our shed in the 80s. Sold webs and whole spiders. Been bit twice. The Bite Feels like a blow torch but the Stomach Cramps later are the worst!
@penobscot7285
@penobscot7285 Ай бұрын
Bros videos keep getting more dangerous
@obnox1ous_3fe420
@obnox1ous_3fe420 Ай бұрын
I mean your not wrong
@toothpaste295
@toothpaste295 Ай бұрын
When: “Touching the demon core till it goes critical”
@jamesshelton308
@jamesshelton308 Ай бұрын
Nah, not really. Black widows and brown recluses almost never bite except when being crushed with no way to escape. The vast majority of them just try to run away. Imagine biting a skyscraper that was picking you up. You might hurt it eventually, but in the short time you're just going to piss it off and it'll kill you. Better to just run.
@toastedtarts4044
@toastedtarts4044 Ай бұрын
@@jamesshelton308a skyscraper?
@bloodiamondeyes
@bloodiamondeyes Ай бұрын
@ toastedtarts4044 Humans are the skyscraper.
@Jay1830
@Jay1830 Ай бұрын
There is a problem in your calculation. You did not take into acount the angle of the silk. When you are lifting heavy equipment, if you use 1 ton slings, and you have them at a 45° angle, you can only lift 500kg with them.
@fgbhrl4907
@fgbhrl4907 Ай бұрын
+1 Yep. Was going to comment the same.
@BenAlternate-zf9nr
@BenAlternate-zf9nr Ай бұрын
It being supported by two threads though (left and right), at close to a 3/4/5 triangle, so the normal force in one thread would be about 5/6 of what he measured. Pretty close in this case since the mistakes approximately cancel out.
@davidfulton179
@davidfulton179 Ай бұрын
What a depressingly pedantic take on an attempt to bring basic science to public forum. This is basic science communication, not a high-level MIT material sciences lecture. If he was performing original science you might have a point, but all of your concerns have been addressed in the hundreds of peer-reviewed studies performed over the past 54 years. ALL this content provider is doing is providing an illustration of how the fundamentals of AN approach to the process of experimentation works for a general audience.
@Jay1830
@Jay1830 Ай бұрын
@@davidfulton179 "Tolerance will reach such a level that intelligent people will be banned from thinking so as not to offend the imbeciles." - Dostoïevski
@aYTperson
@aYTperson Ай бұрын
@@davidfulton179 when a post starts off with "pedantic"...what a snobbish way to insert yourself into a conversation. this content creator appreciates feedback on his work. just because you didn't come here for MIT level material science doesn't mean the content creator doesn't appreciate the feedback.
@okayolamax2min345
@okayolamax2min345 Ай бұрын
The Action Lab is one of my favourite channels... in fact measured over time - The Number One - due to too many consistent variables to mention... down-to-earth enquiry, passion, scientific methodology, good humour... Cheers & thank goodness for Action Lab
@skeleglitchgaming
@skeleglitchgaming Ай бұрын
Man, them spiders be acting like engineers at this point
@Demonic_Tang
@Demonic_Tang Ай бұрын
Nature's best engineers. Termites are second, ants and bees tie for third
@skeleglitchgaming
@skeleglitchgaming Ай бұрын
@@Demonic_Tang facts 😆 Edit: you could even call termites experts in demolition aswell
@dingus42
@dingus42 Ай бұрын
@@Demonic_Tang beavers are pretty good too
@KhattaRapidus
@KhattaRapidus Ай бұрын
@@Demonic_Tang You forgot the different bacterium species which process types of cement?
@ChewyTwee
@ChewyTwee Ай бұрын
Haha they are technically the deadliest North American Spider but out of around 2.5K Bites reported to poison control only 4 to 8 people die from bites per year, and usually those with aggravating factors such as immunodeficiencies. Also keep in mind that there have been 0 *confirmed* black widow bite related deaths since 1983, unless someone actually captures the thing that bit them and has it checked by a professional it can't be considered a 100% confirmed case due to the frequency of misidentifications. In many cases people don't even know what bit them which is fine, but it's hard to take stats from poison control calls alone. Spider bites should be about as scary as thunderstorms because you're actually more likely to get struck by lightning then die from a spider bite.
@amicaaranearum
@amicaaranearum Ай бұрын
Black widows are also very chill. There is a paper called “Poke but don’t pinch: risk assessment and venom metering in the western black widow spider, Latrodectus hesperus” where they looked at the conditions most likely to provoke a bite. In short, they generally don’t bite when poked, only when pinched. More than 50% of defensive bites were dry bites (no venom). Spiders also delivered less venom in response to less threatening situations. So a black widow you can see poses virtually no threat to you. Most defensive bites result from accidental encounters with a spider in an unexpected location.
@MitzvosGolem1
@MitzvosGolem1 Ай бұрын
Angle made of strand between supports changes horizontal tension force. The less the angle the greater the horizontal force which can be far far greater than the vertical weight of the hooks you placed on strand. In Statics physics. At 45° horizontal and vertical forces are equal. An accurate strength test can only be made using pure vertical strand . Or measurement of angle of strand upon failure.
@j.mtherandomguy8701
@j.mtherandomguy8701 Ай бұрын
That is irrelevant, tensile strength is measured by how much it can withstand, not how much force it produces from tension, the horizontal component here is hence excluded from the calculation as the sample doesn’t “withstand” it.
@MitzvosGolem1
@MitzvosGolem1 Ай бұрын
@@j.mtherandomguy8701 I know . But the actual force applied varies with change in angle . Basic statics in physics structural engineering. You seem to not understand my point. If he hung a known vertical weight on silk strand it would be a pure linear equation pure vertical force A horizontal cable when loaded becomes a differential equation since the weight stretch cable increase angle decrease horizontal components increase vertical. At 45° both are equal. One can measure exact force on strand only by knowing the angle it makes from horizontal. At 3° the tension is much much higher than at 45° .
@hannahnelson4569
@hannahnelson4569 26 күн бұрын
This is true! The angle does significantly affect the tension!
@MitzvosGolem1
@MitzvosGolem1 26 күн бұрын
@@hannahnelson4569 statics in physics. Trig used to determine resultant force vectors.
@andrewetos
@andrewetos Ай бұрын
Now I get why Spiderman's web could lift an entire School bus
@ComfortOfori-s5t
@ComfortOfori-s5t Ай бұрын
😂😂😂😂
@skylerthacreator
@skylerthacreator Ай бұрын
0:52 scientists have finally begun to realize they exist
@SerkanKabak25
@SerkanKabak25 Ай бұрын
That ‘kickback’ behavior at 0:08 is characteristic of black widows, I’ve witness them do it towards objects like sticks when pressed against their abdomens.
@Sheenifier
@Sheenifier Ай бұрын
Another characteristic of Black Widows is that they like to pose a lot in almost every situation
@erykmozejko3329
@erykmozejko3329 Ай бұрын
Just did a quick repair on a theodolite cross hairs last week. Black widow silk is highly recommended for these. Good fine consistent diameter with a good strength in order to be fitted accurately and taut enough.
@Graymenn
@Graymenn 10 сағат бұрын
maybe it will help you find the curvature better
@NinjaNezumi
@NinjaNezumi Ай бұрын
You did the test a bit wrong - you're only supposed to calculate the tensile strength from a certain amount of deformation usually labeled at the failure point. When it deforms too much you should stop counting. I think the deformation was certainly past the critical failure point at around 8 - meaning it would've snapped after being left alone for a few more minutes. The failure point was 6 or 7.
@LK-kh5ce
@LK-kh5ce Ай бұрын
KZbin has blue comments now??
@mitchellsteindler
@mitchellsteindler Ай бұрын
I think youre talking about yield strength. Hes testing ultimate testile strength, which is strength at the breaking point. Mechanical testing values can change depending on loading rate, but part of testing is determining the rate you care about before the test.
@willimnot
@willimnot Ай бұрын
@@mitchellsteindler is right
@SillyVrBros
@SillyVrBros 27 күн бұрын
Yo shut up
@leeborocz-johnson1649
@leeborocz-johnson1649 Ай бұрын
One time at summer camp in Tennessee in 2006, there was a black widow nested in the ceiling joists of the latrine of my troop's campsite. I noticed it the 2nd or 3rd day of camp, and just looked up at it, hanging out there, every time I went to have a seat. I knew about black widows but gor some reason I just thought nothing of it and didn't say anything to anyone. No one else noticed it until the last day of camp, when the Scoutmasters called in the camp ranger and the established a friggin' perimeter and no one could go to the bathroom for an hour.
@ClintsReptiles
@ClintsReptiles Ай бұрын
Your methods are so brilliant! Thank you for another fascinating and educational video.
@sinjai1337
@sinjai1337 Ай бұрын
@@ClintsReptiles Clint!
@mstreich
@mstreich Ай бұрын
At this point I fully expected you to ask, “Where did she go?” 😅 1:27
@NardosAddis-tv3sp
@NardosAddis-tv3sp Ай бұрын
1:12 I think that's too much for a spider bite...
@tomedward8652
@tomedward8652 Ай бұрын
A simple back of the napkin calculation shows that to make a tread of 1mm diameter you would need approximately 69,000 spider threads. This is why we don't see everyday object made from spider silk. However, I did once read an article many years ago that said that DARPA (or some military company) had manged to splice spider DNA with Goat DNA such that they could extract silk from the goat milk in larger quantities than they could from spiders.
@nab-v1w
@nab-v1w Ай бұрын
Glycine and other amine from silk oxydate super fast. Also, by going from 4 to 1000 micrometer section, you have 250*250 =62000 so you right on this but you can also toll a 7 cm long thread on it self
@amv240
@amv240 Ай бұрын
A not so subtle issue when comparing strengths of materials is that the concept of tensile strength is “bugged” when it comes to very thin materials (as it is a value that is normalized to area; this is a common problem in STEM). It is true that a spider web “could” hold an airplane, etc. but the usual comparison is pointless when one of the materials is limited to very thin/small dimensions (i.e. not practical at the compared scale).
@yodaiam1000
@yodaiam1000 Ай бұрын
Post tensioning steel can actually have a specified strength of greater than 1.8GPa. You should go into more how you calculated the tension load on the thread when you were adding the hooks.
@undeadarmy19
@undeadarmy19 Ай бұрын
I love how interesting and educational your videos always are. You're really good at explaining things, even complicated things, in an uncomplicated, easy-to-understand way. Thanks for all your hard work.
@tonyf.9806
@tonyf.9806 Ай бұрын
While the spider silk is very strong in tension, we have yet to figure out a way to use it in compression. Also, the durability of it is probably a major factor where even if we could scale it up for construction purposes, steel may still end up lasting far longer.
@Deipnosophist_the_Gastronomer
@Deipnosophist_the_Gastronomer Ай бұрын
Not good for submersibles, then. 😅
@Kraflyn
@Kraflyn Ай бұрын
your experiment measures tangential stress. The thread breaks due to tangential forces, not normal forces. The tensile strength, due to normal forces, is usually at least 10 times larger than the tangential stress limit.
@harlanweid7723
@harlanweid7723 Ай бұрын
Incorrect, since the string is flexible, in the region outside weight hanging at (failure occurred outside that region), forces are directed along the string. If it is about the anchoring region, things are more complicated (very hard to know exactly because it involves adhesion and non-elastic properties of the string) and still far from pure shear, but since the string thinnens, i believe it fails outside that region too.
@amosbackstrom5366
@amosbackstrom5366 Ай бұрын
Still, I think it would have been more accurate if he attached the silk to a weight on a scale. Then he could just slowly pull on the silk to see how much weight it could subtract from the scale before breaking. [Edit] Nevermind, I just finished the video and see that he did that too. Very good
@Kraflyn
@Kraflyn Ай бұрын
@@harlanweid7723 Nope. Cut the string anywhere, in mind, and balance the forces, left and right. There is no section of string, due to the shape, without tangential forces. And the tangential strength is much weaker than the tension strength. Yeah, the proposed weight on a scale experiment would eliminate tangential forces.
@harlanweid7723
@harlanweid7723 Ай бұрын
@@Kraflyn The string is in uniaxial uniform tension state far enough (~2 diameters) from the weights and the anchor. It is due to Saint-Venant's principle (you can find it in wikipedia or elsewhere). Consequently, the cross section without tangential forces will be the one normal to the string.
@Kraflyn
@Kraflyn Ай бұрын
@@harlanweid7723 No... Just do the cutting trick from Technical Mechanics... The applied outside force is the weight in the middle of the string, acting downwards. String is horizontal att he center, and at an angle but almost horizontal elsewhere. At no point is string vertical too. So the reaction is vertical too, because the outside force + the reaction cancels out: the equilibrium principle. So the force in the string is vertical too. But string is almost horizontal... so the stress in mostly tangential... nothing can possibly convert a vertical force into a horizontal one... Just:no! :D
@UncleKennysPlace
@UncleKennysPlace Ай бұрын
I had an unused basement door (with old oak steps, from the early 20th century) and I decided to remove the rotten (never in the sun) steps. It turned out to be a black widow farm. There were dozens of them. I'd only seen one or two in the wild before that. Yeah, I grabbed one and looked at its belly.
@Doing_Time
@Doing_Time Ай бұрын
We have thousands of those around our property any given summer day/night, they love building webs on steel. Never been bit by one (have been bit by tarantula, which was most painful bite of my life by far), but many on me one way or another. Nothing as creepy as the feeling of those strong widow webs tugging on your ankles or face as you walk around in the dark...
@arrowghost
@arrowghost Ай бұрын
For the record from Mythbusters Jr : 30μm of steel thread = 39.3g to break 500 Golden Orb Weaving Spider's silk strands (Same density as 30μm steel thread) = 83g
@GIGACHAD-jj3wl
@GIGACHAD-jj3wl Ай бұрын
I love the fact that at the start he says "it's the deadlist spider" then proceed to touch it
@AudioThrift
@AudioThrift Ай бұрын
There was a black widow that lived on our porch for about a year and a half which my wife named "Elvira". I'm a tattoo artist and every time a client wanted a black widow tattoo, I would take pictures of her and use them as references. That one spider has been immortalized on at least 15 people.
@marineastro
@marineastro Ай бұрын
I'm not convinced that just because you apply a tangential load doesn't mean that the silk isn't experiencing axial loads(and I don't mean axial loads from bending). I believe that the silk is indeed experiencing axial loads as the material isn't like an aluminum or steel beam. Therefore, the typical analysis that you'd do with transverse loads, which involve calculating the shear load and then the moment diagram and then calculating the bending stress and shear stress, won't be applicable here because the silk isn't experiencing bending stress. I know that these mechanics of materials calculations are only applicable when the material in question fits certain criteria. We also need to consider whether the silk is experiencing plastic deformation or elastic deformation. Also, these stress calculations are usually under the assumption that the cross sectional area is constant under all loadings. Technically, if the silk is extending substantially longer, then due to conservation of mass, the cross sectional properties have to decrease to accept a longer piece of silk. Lastly, you need to look at the internal loads by taking a ''cut'' at two ends of the spider web and resolving the tensile loads based on the angles made with either the horizontal plane or the vertical plane. As another guy said here, the tensile load here is 5/6 P, assuming a 3/4/5 triangle. What we don't exactly know exactly is what radius The Action Lab used in the cross sectional area calculation, or what type of rounding that may have been done. These ramblings coming to you from a dude with 4 years of stress analysis experience, so please take what I write with a grain of salt.
@yousefaljarrah6625
@yousefaljarrah6625 Ай бұрын
7:48 yes microscope, the thierd deadly spider and a gold balance are all a very simple tools that you can found in ALMOST every home
@vind302
@vind302 Ай бұрын
True story: As I’m watching this video I spot a spider walking on the floor that’s dark brown but has a pattern on its back. Is it a black widow!!? I took a picture of it and with the new iOS you can press down on the image and it gives you the option to look it up online. I looked it up and it was only a Triangulate Cobweb spider. Modern tech is a marvel!!
@Mountainmonths
@Mountainmonths Ай бұрын
yeah Steatodas or 'false widows' are really common inside homes but they like to hide in very dark corners like behind bookcases. they are good bugs and catch moths and such
@potatosordfighter666
@potatosordfighter666 Ай бұрын
Go use that tech on a mushroom and see how long you live.
@arrowghost
@arrowghost Ай бұрын
"So are we going to, build a building out of spider silk and compare it to a building made of steel? NOPE. The best place to start is to look for a form factor of steel that matches the form factor that spider silk comes in." - Adam Savage, Mythbusters
@cellman1829
@cellman1829 Ай бұрын
I hate when people kill spiders or other things 😮. I'm glad you took it. Just put it in a cup and let it outside , they kill annoying insects like flies, cockroaches, crickets etc. This is what I do , I sometimes get scorpions I just let them back outside. They want nothing to do with humans.
@officermeowmeowfuzzyface4408
@officermeowmeowfuzzyface4408 Ай бұрын
Ikr they behave like most other arthropods and are either timid or afraid of us
@cristinelcostachescu9585
@cristinelcostachescu9585 Ай бұрын
Until you step near one in your backyard...
@cornfarts
@cornfarts Ай бұрын
I dont mess with them they dont mess with me. I have a lot of them in my back yard
@Doing_Time
@Doing_Time Ай бұрын
what your saying is totally irrational...she's literally going to murder her mate and thousands of "other things", in the most painful and frightening of endings
@amicaaranearum
@amicaaranearum Ай бұрын
Black widows are very chill. If you’re aware of a widow’s presence, it poses virtually no threat to you. They only bite defensively as a last resort, usually when pinched. In one study, more than 50% of defensive bites were dry bites.
@melba5337
@melba5337 Ай бұрын
My brother and his teenage friends had a pet black widow they kept in the shop. They fed it other bugs or spiders that tried to make their home there. One day one of the boys had caught a strange looking red spider that they put in there. It was smaller than she was but she was terrified and it killed her. Shocked us all. We looked for pictures online but I don't think we ever figured out what the red spider was.
@bubbabot6049
@bubbabot6049 Ай бұрын
Carnage
@kwinvdv
@kwinvdv Ай бұрын
When calculating the tension in the spider silk in the first experiment, you also need consider the angle the silk is making (because it is slacking due to the weight). From the video I estimated this to be around 30° with respect to the horizontal, resulting in an estimate of the tensile strength of 1.2 GPa.
@jkddaddy
@jkddaddy Ай бұрын
Ultimate tensile strength is a sexy engineering and intuitive measure but another key property that goes hand in hand is the ductility. In other words how much stretch does the strand have before failing? This would be super interesting to compare to the other materials you reference. You’ll notice that in most cases higher strength materials are also a lot stiffer or less ductile.
@crassbusinessman3122
@crassbusinessman3122 Ай бұрын
This is the deadliest spider in the world 'Touches it' Bro wtf are you doing? XD
@sachiperez
@sachiperez Ай бұрын
i love it when you explain the methods you use, measuring pixels and all!
@electronicmt._.3138
@electronicmt._.3138 Ай бұрын
How can we get that web size steel wire ?
@colematuschka9252
@colematuschka9252 Ай бұрын
My Australian Redback spider that I had about a decade ago seemed to have much stronger webbing compared to a regular black widow.
@NotSoMuchFrankly
@NotSoMuchFrankly Ай бұрын
"If I were bitten by a radioactive spider..." Bro, trust me. You don't wanna see where the webs come out.
@youravghuman5231
@youravghuman5231 Ай бұрын
2007 : "I wanna get bitten by spider so i can shoot web from my hand 😃" 2024 : "Please don't bit me spider, I don't wanna produce organic web 🤮"
@ermatthe
@ermatthe Ай бұрын
We regularly encounter black widows while doing yard work (why I I wear gloves when picking up rocks or leaves). They prefer to live outside thankfully, so we've never seen one in the house.
@TXHEN1
@TXHEN1 Ай бұрын
Thank you for "risking it all" for us -_-
@ozzybloke4830
@ozzybloke4830 Ай бұрын
We get redback spiders in Australia very similar to the black widow, there are videos on youtube showing redbacks catching snakes in their webs.
@davidfulton179
@davidfulton179 Ай бұрын
We need to stop and appreciate that this 8 minute video was likely took hours and hours and days and day because, among other things, he had to learn how to actually handle and process the silk for his experiments and observations. He likely spent hours combined just locating the silk when it appeared to vanish! And I'm sure that just rigging up the weight test was a massive time suck! All this to demonstrate for the public an experimental protocol that has already been performed at research institutions in order to benefit the communication of science! Bravo!
@AsmaZia-by3vm
@AsmaZia-by3vm Ай бұрын
RUSSIA!!!
@jonathanodude6660
@jonathanodude6660 Ай бұрын
The thought emporium did a video on custom made spider silk a while back. it was pretty eye opening.
@aaronShmackles
@aaronShmackles Ай бұрын
Yea i accidentally picked up a massive one thinking it was a paintball never again
@aboriani
@aboriani Ай бұрын
Damn dude, I started rubbing my hand just reading that
@abdurali8855
@abdurali8855 Ай бұрын
Ohh hell nooo 🫢 🫢
@westulon
@westulon Ай бұрын
Painball.
@aaronShmackles
@aaronShmackles Ай бұрын
@@westulon yea use to play paintball when I was younger and in the field I thought one was one
@aaronShmackles
@aaronShmackles Ай бұрын
Scared the crap out of me
@amicaaranearum
@amicaaranearum Ай бұрын
Despite their venom, black widows are very chill. There is a paper called “Poke but don’t pinch: risk assessment and venom metering in the western black widow spider, Latrodectus hesperus” where they looked at the conditions most likely to provoke a bite. In short, they generally don’t bite when poked, only when pinched. More than 50% of defensive bites were dry bites (no venom). Spiders also delivered less venom in response to less threatening situations. So a black widow you can see poses virtually no threat to you. Most defensive bites result from accidental encounters with a spider in an unexpected location.
@noobfart
@noobfart Ай бұрын
one day bro is going to end up in a youtube documentary "what happens when experimental science goes too far" 😭
@williamplaygaming3555
@williamplaygaming3555 17 күн бұрын
My grandma got a cabbage and then a black widow come out of it she was yelling until she had to find it because it got missing and we bought some bug spray and we sprayed so much we couldn’t breath in the house so we had to rent a motel for 1 night. Hope you guys like the story
@Shady_br
@Shady_br Ай бұрын
No way you managed to get Scarlet Johansson in one of your videos
@logitech4873
@logitech4873 Ай бұрын
Who?
@ElectroTree01
@ElectroTree01 Ай бұрын
You should’ve done it straight up and down because the angle changes the amount of force exerted as tension compared to weight. At 30 degrees each side experiences the weight of the suspended object but at 90 degrees, each side only experiences half so it can change a lot depending on the angle.
@lukkagge
@lukkagge Ай бұрын
0 views in 67 nanometer cmon man
@subbrn
@subbrn Ай бұрын
Nanoseconds you mean, right?
@sora6303
@sora6303 Ай бұрын
When I was really little, my Dad and Papa taught us how to spot black widows and where to find them. We went on black widow hunts every summer and my Papa would always say that I was the best at finding them lmao. I don’t have any degrees or anything like that, but my knowledge stemmed from my fascination, I am very good at finding spiders and seeing their webs because once you know what to look for, you see them everywhere
@blackcracker998
@blackcracker998 Ай бұрын
0:30 tinnitus warning
@JohnWilczewski
@JohnWilczewski 19 күн бұрын
True
@TBNAfrangsYT
@TBNAfrangsYT Ай бұрын
4:02 Black Widow themed villains CONFIRMED?!
@heartdyedpurple
@heartdyedpurple Ай бұрын
1:14 prescription side effects
@longjohnpilsners7750
@longjohnpilsners7750 Ай бұрын
I have a black widow in my backyard (I call her Sheila) and occasionally I have to brush away her webs to get to a light switch and let me tell you, that shit is tough.
@nosowl
@nosowl Ай бұрын
Using weight in a hammock will cause the strand to have much more tension. The strand would experience not only the vertical pull from the weights but horizontal pull from both anchor points.
@AddyAdderson
@AddyAdderson Ай бұрын
At 2:59, I can't hear a thing you say, because my mind is ablaze with the question, "now where the hell did that spider go?"
@brian_belmont87
@brian_belmont87 Ай бұрын
At Lockheed martin in Palmdale California skunkworks they tried to make ballistic vests made out of this silk. It was far to expensive and slow to make. However the tested plates had bullet dust on them from the impact points and was virtually undamaged going all the way up to 308. win mag and it was extremely light weight.
@kaltkalt2083
@kaltkalt2083 Ай бұрын
I asked out loud (to myself) "hmm what about glass, like a drawn-out fiber optic?" and not a second later you put on the next hook and said "stronger than glass". Nice.
@JaisonBuilds
@JaisonBuilds Ай бұрын
Some issues with your first test setup. Since you are applying load while the silk is horizontal, you need to factor the sine of the angle after the load is applied. This means that you're applying much more force to the silk than what you're placing on it in wire hooks
@ldkmelon
@ldkmelon Ай бұрын
The thing with black widows is they have a bad bite but aren't aggressive. We had approximately ninety million of them living in our detached garage when I was in a dessert area and they never wanted anything to do with you, give them time to run away when you start rummaging through stuff and you are good haha
@FiddleSticks800
@FiddleSticks800 Ай бұрын
I am an engineer and a former silk researcher, writing my PhD dissertation about silk. What isn't common knowledge is 1) spider silk isn't stronger than steel (look up tensile strength calculations). 2) If you are going off of tensile strengths normalized to weight, synthetic polymers (UHMWP and Kevlar) are way stronger. 3) It is marginally tougher than synthetic polymers (energy dissipated before failure). But this toughness, is 100% dependent on the hydrated state of the silk. If the silk is wet in the slightest, it looses its toughness as water plasticizes the non-covalent sacrificial bonds (primarily hydrogen bonds between the peptide backbone) which give rise to the yield point and energy dissipating properties of the silk. In short, spider silk researchers sensationalize the topic and are intentionally misleading so that they can gobble up grant dollars with flat promises of benefits to humanity. It turns out the public love sensational stories of biomimetics. What spiders achieve is an impressive feat of evolution but the material properties are overstated by researchers to dupe the layman (the public funding their grants).
@TheActionLab
@TheActionLab Ай бұрын
I hear your other points about spider silk not being a practical material. But are you saying that the silk's tensile strength isn't stronger than steel? In this test I did here, and in the published study I mentioned in the video, it is pretty clear that it has a higher tensile strength than steel.
@FiddleSticks800
@FiddleSticks800 Ай бұрын
@@TheActionLab, what you showed was really cool. So we are on the same page, tensile strength ( a defined materials science term) is reported as the pressure, a force over a crossectional area, at which failure occurs. High performance steel cables are typical made of Extra Extra Improved Plow Steel (EEIPS) with a reported modulus of 2160 N/m^2 for example (2.16 gigapascals). EEIPS steel cables aren't even the strongest. This is higher than the tensile strength of all reported silks and double the tensile strength you reported. Steel has bested spider silk, in terms of tensile strength, for several decades now which is why silk researchers started saying it was stronger when normalized by weight or saying that it was the toughest material known. The later ('toughest Material" claim) is technically true as of the last time I checked. Toughness is the area under the stress strain curve and represents energy dissipation. Although this toughness requires silk testing at fast pull rates and optimal humidity to best high modulus synthetic fibers.
@Industry-insider
@Industry-insider Ай бұрын
One way you know a black widow is somewhere is the web, not just how it is arranged so sporadically, but how it also kinda pops when you tear it
@jesusislord2503
@jesusislord2503 Ай бұрын
Felt something crawling on my face while I was sleep once as a kid did the face slap and woke up with a dead black widow next to my head.....I have and will never forget that.
@RockyPondProductions
@RockyPondProductions Ай бұрын
I understand why you had the strand of web extended horizontally due to the logistics of this experiment. But as a result, the web is not being strained in tension. This is actually a 3 point bending test. When the material is constrained like this, it will break below its ultimate tensile strength due to the inherent flaws in the material. In 3 point bending, different sections of the material are experiencing different stresses. If a flaw is found in the aeras of higher stress, it will fail there. When a part is loaded in pure tension the whole thing is under the same load which helps compansate for the flaws. Also, the load not being applied in a static fashion is skewing (constant rate) the results. As it stands not much can be done in this case since the web is so fine and hard to work with. Overall, great demonstration!
@1mremington
@1mremington Ай бұрын
This is why we named our team, competing in NASA's Space Elevator Tether Challenge, Astroaraneae! We hold the title for strongest tether, besting Sandia Labs employees, MIT researchers, and other top notch competitors. Some people wondered if we were using spider silk made by genetically engineered goats. We did not. Good video!
@ohbeardedone9253
@ohbeardedone9253 Ай бұрын
What did you use?
@1mremington
@1mremington Ай бұрын
@@ohbeardedone9253 Our proprietary material was never disclosed; and I am not at liberty to say. It was stronger than spider silk, for its' weight. An aim of the competition was to utilize the potential strength of carbon nanotubes in a novel material.
@CedroCron
@CedroCron Ай бұрын
You sir are nuts for messing with one of these... YIKES!
@hugodesrosiers-plaisance3156
@hugodesrosiers-plaisance3156 Ай бұрын
I can say pretty confidently that I would much prefer handling a bar of plutonium than a black widow for 2 main reasons: 1- There's appropriate equipment and safety procedures for plutonium 2- That spider is now somewhere in your house
@Spiderjin
@Spiderjin Ай бұрын
Wow, that was an awesome experiment! I never would have thought that spider silk could be that strong. It makes me want to learn more about spiders and their webs. Keep up the cool videos! 👍🕷
@domvasta
@domvasta Ай бұрын
They're such beautiful gentle spiders, they're very hesitant to bite, and if you're an adult, there's basically no way you're dying
@amicaaranearum
@amicaaranearum Ай бұрын
This. Black widows are very chill. If you’re aware of a widow’s presence, it poses virtually no threat to you. They only bite defensively as a last resort, usually when pinched. In one study, more than 50% of defensive bites were dry bites (no venom).
@justinw1765
@justinw1765 Ай бұрын
I'm pretty happy with highly oriented/crystalline UHMWPE fibers. Hopefully industry will eventually be able to make them smaller than 50 denier, so that we can get tarps, tents, windjackets, etc made out of the pure woven stuff.
@IceManTX69
@IceManTX69 Ай бұрын
I've had two widows in my garage in north Texas this year. The web is crazy strong if you aren't prepared for it. It almost took the broom out of my hand when I went to brush away the first one. With more force it gave way, but you could actually hear it tearing, which was crazy. I've taken hundreds of bee stings but this freaked me out quite a bit. lol
@DeveloperChris
@DeveloperChris Ай бұрын
Every garage and verandah in Australia has dozens of redback spiders. Our version of the black widow. Its why we wear gloves when working around piles of wood and other areas they like.
@Alasdair-Morrison
@Alasdair-Morrison Ай бұрын
Similar to our Australian Red Back spider, Nasty little FKR's They setup camp inside your shoes, Dunny (toilet) or anywhere dry.
@Randomactivities2.0
@Randomactivities2.0 Ай бұрын
I was just cleaning my shop and there were dozens of brown widows(*BW) and grandpa long legs(*GPLL). I observed the brown widows capturing the GPLL. It was crazy because they would let a leg fall off to get away. The brown widows were fishing by the looks of it. The GDLL would get snagged then the BW would run back and forth attaching silk to the leg, and every time the BW went back up the web it pulled in the GPLL a little more until the BW got it or the GPLL leg popped off. Needles to say I didn't get much cleaning done.
@edweinb
@edweinb Ай бұрын
Anyone who has accidentally walked into a black widow web can testify to the strength of the strands.
@-qj6ps
@-qj6ps 29 күн бұрын
I’ve been bit by a black widow on the hand and my heart started jumping or palpitating. I went to the ER but they just had me sit there and wait it out.
@chaselarson4224
@chaselarson4224 Ай бұрын
In Southern California, we also have brown widows and white widows. And the rear occasion , a brown recluse
@RaymondBCrisp
@RaymondBCrisp Ай бұрын
My mind was blown by this fact I discovered some 40 years ago in engineering school. Of course, it was during a lecture on tensile strength versus rigid strength, so it was quite relevant. When we performed a test with a hydraulic press equipped with sensors and a cable make from the silk (no idea what species though), we found it to possess tensile strength approximately five times stronger than steel. Truly amazing stuff.
@zackpedersen2666
@zackpedersen2666 Ай бұрын
Just some more information for people who want to learn more about the Widow genus of spiders and deadly spiders in general. The Brazilian Wandering Spider and the Sydney Funnel Web Spider are numbers 1 & 2 as deadliest true spiders in the world. Widows (Latrodectus sp.) are number 3. Both widows and recluse spiders are non aggressive and are very reluctant to bite. The only time they bit during scientific studies was when they were pinched or squeezed in some form. This coincides with the vast majority of bite reports where someone got bit on their foot when putting a shoe or boot on, or if someone grabs something, not seeing the spider and getting bit on the hand, or even on a toilet or in bed when someone unknowingly sits on, lays on, or otherwise crushes the poor spider causing it to bite as a last resort. The black widow that participated in this study Latrodectus hesperus is the Western Black Widow. Widow bites are medically significant, however; most people will recover with basic medical care such as OTC pain relievers. Young children, elderly people, immunocompromised people, and people with allergy to the venom should seek emergency medical help. Lastly, these spiders are quite beautiful to behold and there are many keepers that have them in their collections. I personally would like to have an individual that shares the same name as my wife’s favorite marijuana strain. Latrodectus pallidus, the White Widow.
@thundergamergd
@thundergamergd Ай бұрын
"this is the deadliest spider in North America" Casually touches it
@Fugleebogan
@Fugleebogan Ай бұрын
The thick gold strands of an Aussie orb weaver would be worth checking.
@jamesco4942
@jamesco4942 Ай бұрын
I would make ropes out of the stuff from off the walls in my garage, it would only be about two inches long but as a kid I wasn’t strong enough to brake it
@nicholasrowan387
@nicholasrowan387 Ай бұрын
This is a crazy coincidence, I literally saw a black widow in person today, and it was the first time too
@Csj597
@Csj597 Ай бұрын
I've watched you for years but this video is one of my favorites.
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