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Bomb-Proof Wallpaper Developed
MikeChino writes "Working in partnership with the US Army Corp of Engineers, Berry Plastics has rolled out a new breed of bomb-proof wallpaper. Dubbed the X-Flex Blast Protection System, the wallpaper is so effective that a single layer can keep a wrecking ball from smashing through a brick wall, and a double layer can stop blunt objects (i.e. a flying 2×4) from knocking down drywall. According to its designers, covering an entire room takes less than an hour."
Rhino liner works great
It is meant to be installed with anchors. It would remain stuck to the wall and stop shrapnel fine without them, but when the wall bows, the tape would bow with it, causing a collapse. The anchors make the tape provide tension that keeps the wall up. Here's a video about the stuff that will clarify.
Eh.
Really, it's useless for hurricanes, aside from in places where people wouldn't be prepared for a hurricane anyway.
At the very least, Florida's building code is such that, for anything built in the last 17 years (at least - I know the standards were strengthened after Andrew), the wind causing impacts is not what does damage - Aside from to windows. It's the the wind speed and pressure differences that destroy roofs and cause structural damage, and flooding that causes the most damage, really.
Whoo, being a Floridian does have it's uses.
Mail (chain) armor was generally less useful against arrows than plate to start with... that is one of the reasons that plate armor was developed in the first place. But if you think that mail armor was often a supplemen (worn under) plate armor, you are mistaken. It might have been in rare instances, but in general plate armor was enough of a burden that any other metal would have weighed far too much and further hampered the warrior's effectiveness in battle. Plate was the "ultimate' body armor. It may have had some mail at weak points such as armpits but in general mail and plate were not worn together.
This seems to be a common misconception, probably due to it being taught badly in schools. Taking an aeroplane as a specific example since this is the most common example of lift. You will find that the Bernoulli effect (the lift generated by a pressure difference above and below the wing) is not the main reason why planes fly (although the effect does exist, it is just not a large enough force to keep a plane up).
What demonstrate this most clearly are symmetrical winged aeroplanes which are things like stunt planes which often fly upside down. It should be evident from the fact the wing is symmetrical that the common explanation of lower pressure above because air goes around a curve making it go faster has zero effect here.
If you have paid attention carefully when flying you may have noticed that a plane does not fly completely flat most of the time. There is a small angle between the planes wings and the direction of travel. Because air tends to follow the surface of the wing (sometimes called the Coanda effect) this means that the air gets deflected downwards by the wing. If the air accelerates down then by Newton's laws there is an equal and opposite force upwards on the plane generating lift so it can then fly.
I have not read anything about how houses are affected but I would imagine it would be a similar effect with the roof deflecting air causing a force.
Okay, having looked this up again (I hadn't for some time), I will have to back down from my position that the longbow killed plate armor. But the longbow did demonstrate that it was no longer the panacea it had been (as at Agincourt and other examples), and it gradually faded starting about then, through the advent of early firearms, and basically died in the form of full-body armor not long after.
While I am not "calling bullshit", as it were, I find the story of the silk armor to be a bit incredible. I am pretty familiar with silk and its properties. I am not saying it was not popular, or that there were not stories, but I seriously question the effectiveness of any quantity of silk that anyone but a "noble born" could afford, as armor.
What I can say with authority, however, is that kevlar, by itself, is not and has never been particularly effective against "firearms" in general. It can prevent the penetration of certain handgun rounds, but by no means all, and still allows considerable damage to the wearer. For the most part kevlar vests were worn by law enforcement and the military to reduce damage, not prevent it. Even for the handgun calibers that kevlar would normally stop, pointy jacketed and/or hardened slugs can still penetrate kevlar like butter. Even relatively low-power rifles will punch straight through a kevlar vest.
However, the combination of kevlar and high-tech ceramics ("Dragon Skin" is probably the best example) can withstand a hit from a relatively high-powered rifle, and with relatively little damage to the wearer. Especially if some of the newer aramid-type fibers are used instead of kevlar. But those developments are VERY recent... no more than a few years.
Um, you might want to check your history again. The longbow was the weapon that made plate body armor obsolete.
Actually it wasn't. Plate armor was widely used in Europe after the Battle of Agincourt in 1415; arguably it gained in popularity.
It was very difficult to pierce plate with a longbow. The English victory at Agincourt is more due to the terrain than anything else; arguably plalte became even more popular after Agincourt, precisely because it offered reasonable protection against arrows. (Protecting horses etc. was another matter.) The crossbow did a much better job against plate armor. It delivered more kinetic energy, and it took much less time to train a crossbowman than a longbowman. Firearms did the rest in the 15th and 16 century. The single most driving factor, however, was cost - plate armor was too expensive to make and maintain, and if you can hire a whole squad of Landsknechts (arquebusiers, what have you) for the same money it takes to have plate armor made for yourself, the arquebusiers win. At that point, however, longbows had already been obsolete for more than a century.
As a state gets corrupt, its laws multiply; the most corrupt states have the most numerous laws. (Tacitus, Annales 3:27)
This, also, is misleading. Some of the most spectacular remaining samples and artwork of armor are plate, but are for _jousting_. Like modern bomb-proof armor, what is worn for such a specialized use is far bulkier, more expensive, and heavier than actual combat armor. And even the best plate was often supplemented at joints such as knees and elbows and hands, with chain where making joints out of plate would be too awkward or expensive.
Also, the better plate of the Middle ages was certainly capable of stopping the ordinary "clothyard shaft" of the longbow. The tips of the clothyard shaft were typically rather soft, inexpensive steel: it _flattens_, bends, and glances off with even a quite direct hit on a good quality breast plate or helmet. (Yes, I've seen this tried.)
It is misleading to say "the bow and arrow drove the change" when the bow and arrow predate civilizaiton: plate armor does not. Other factors include the introduction of the _inexpensive_ long bow: the price of a single armored knight was easily undercut by the price of 20 farm boys with bows, and they could produce an arrow storm that would not only kill the knight's less armored steed, but was likely to put clothyard shafts in his joints. Couple that with a muddy field where a knight's boots and heavy armor will bog down, such as occurred at Agincourt, and the yeomen with daggers could easily beat the French knights to death, force their visors into the mud to drown, and shove daggers into their eye slits.
The concept of "plate" long predates the middle ages, remember: even the Greeks and wealthiest Egyptins had breast plates or bronze, quite effective against the weapons of their time. Their efforts were limited by weight and the strength of the metal, but it was certainly the ancestor of "plate".
Yep, according to "Time team" their steel boots got stuck in the mud at Agincourt (like gum boots do), the English ranks were mostly wearing rags as shoes and could move more freely. Longbows were the WMD of the middle ages, especially when you had 10K archers all of whom could fire fast enought to keep 3 arrows in the air at once. Such a volley of arrows flying through the air is said to make a roar that could be heard for miles. As to wether they were effective against armour apparently that depended on what type of metal the amour and arrow heads were made of.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
This is an issue that has been much debated, and to the best of my knowledge not yet firmly decided.
No, it is not an issue that has been debated. The practical aerodynamics of airfoils is very well settled.
If you have paid attention carefully when flying you may have noticed that a plane does not fly completely flat most of the time. There is a small angle between the planes wings and the direction of travel. Because air tends to follow the surface of the wing (sometimes called the Coanda effect) this means that the air gets deflected downwards by the wing. If the air accelerates down then by Newton's laws there is an equal and opposite force upwards on the plane generating lift so it can then fly.
1) This has little to do with the Coanda effect. 2) While there is momentum imparted onto the lower surface of a wing at a positive angle of attack, pressure distributions along the surfaces dominate the behavior of the airfoil. Air is slowing down when it follows the lower surface of a flat plate, and speeds up along the top, which gives (gasp) a pressure differential.