h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Can the glass withstand a shot that hits the exact same spot as a prievious bullet, Stragbasher? You said that the brittle glass shatters on the strong side to absorb the shot but what if this has already happened and there is just the flexable material for the bullet to pass straight through? If a second shot would puncture a hole then the glass wouldn't be very good against automatic weapons so mayby you could explain what would happen. Cheers.

A fully automatic weapon fires fast... but there is still a decent amount of spacing between bullets (I seem to recall something like say... 10 meters between M-16 style bullets..) Guns also have this nifty thing called recoil, so hitting hte exact same spot twice isn't overly easy. Also, just because the brittle layer breaks doesn't mean it falls out of the window... it might just eggshell but remain glued to the flexy layer... this means that there will still be shaterable glass to help dispurse further shots.

Course, I don't make the stuff, so I'm not sure.

Also, if some joker fired a bullet at my bullet "resistant" glass window, I wouldn't be standing in the same place for very long... so even if the same spot was hit twice, the target might be smothered under Swiss guards.

Also, it should be noted that even when a normal bullet is fired through a window, the act of hitting the glass causes the bullet to change direction slightly... so the bullet doesn't travel straight through and stands a decent chance of not hitting what it was aimed at. Even when penetrated by the first shot, I would imagine a bullet would be misdirected until a decent hole was made in the glass for bullets to fly through. I'm not sure how this would effect 'outgoing' bullets... presumably it would cause them to not go exactly where they were supposed to... 'Cept if you're a Texas bank guard and you just fired a shotgun... might not matter.

'Course, I don't like guns.... I'd perfer people either use big clubs, sharp rocks.... or lasers. A laser could burn a pope in a pope-mobile made of bullet resistant glass with relative ease... of course a laser big enough to make Pope-Toast wouldn't exactly fit under your hat or be purchased at your local (my local) K-mart.

I'm a physics major... can you tell? :+)

Glass does change the direction slightly. When police/military snipers have to shoot thru glass, 2 people shoot at almost the same time at the same aiming point. The first bullet breaks the glass, the second goes thru unobstructed before the target moves in reaction to the glass breaking.
It's impossible to hit the same spot twice w/ full auto, because the recoil throws it (way) off. Full auto is to keep the enemy's head down. If you want to hit the anything, it has to be single, aimed shots.

Now that I think of it, I saw a demonstration on a TV show. Somebody fired a 9mm submachine gun (H&K MP5, I think), an M16, and a 12 gauge shotgun into bulletproof glass. No 2 full-auto bullets hit anywhere near the same spot, and the lead mushroomed to fill the hole it almost made. The 'glass' caved in like an eggshell around the impacts, but stayed in the window.

What if you built your laser at the local power plant, tapping it for power there, and having a long glass fiber cable leading all the way from the laser thingy to your hand+

Can you fire a laser through any kind of window, or will imperfections in the glass scatter the laser too much, spreading out it's energy making it useless?

Also, could you burn a hole in a pane of glass with a laser?

And what would happen if you fired a laser at a mirror? Would it melt the mirror, or the target it was reflected to? I assume it would melt the target, but I don't know.

then you'd probably get caught

lasers difract when they go through glass, but that level of difraction can be calculated (unlike a bullet flying off target in an essentially random direction).

If a mirror or piece of glass was too impure and the laser was sufficiently powerful, then the glass/plastic/mirror would melt or burn... but I think that if you can see through a piece of glass or see an image in a reasonably well constructed mirror, a significant portion of the energy of the laser will continue onwards... a piece of glass or mirror with the wrong shape might cause the laser to loose confinement (spread out so its energy is spread over a larger cross-sectional area and hence doesn't do much). Likewise, a mirror made from a strip of tinfoil would probably just fizzle if hit by a decent laser.

Of course, I mentioned lasers mostly in jest... its sorta like suggesting using a cannon to knock down a stone wall... sure it'll work, but its not terribly efficient.

Thankyou very much, Mr. Trenchcoat. I have made a note to get some of this glass when I am rich enough for enyone to want to shoot me.

Well, if you were rich enough for someone to want to shoot you, then it's only your heirs that'd want you dead. No one else would really benefit either way. Of course, if you were really powerful, then a lot of people might want to kill you, because then they might get your power, or you wouldn't have power over them, or something like that. Of course, because I haven't got the faintest clue who you are, I really can't estimate how likely that really is.

I ment rich and FAMOUS. If I was famous then there is a chance that people would want to shoot me and this chance would increace ten times if I was a rap star. Of course my comment was just a stupid hypothesis and i dont even know why i'm bothering to correct myself.
Enough!

Okay.