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[Moddan]

ok, wait, im having trouble understanding everything you want to say. also, after reading what i wrote again, i realize its kinda sounding strange. what i mean is _not_ to approximate the equation F=m*a with F=m*v _but_ to estimate the damaging potential of a projectile by using its impulse p=m*v.
next: when a bolt is in the air, then youre right, there is no force. but while its in the process of hitting its target, a force is being applied, on both the
bolt as well as the location on the target, where it strikes. the bolt is applying force for a very limited time, yes, but its a finite time which does not equal zero. when swinging a weapon in close combat you can stay in contact with the target much longer, but that does not mean its in any way different from a projectile in regards to applying forces.

I think the momentum is not good to describe the damage potential. If look at a projectile with a speed v and a mass m you can calculate both the momentum p=m*v and the kinetic energy E=1/2*m*v^2. So if you double the mass, you double energy and momentum but if you double velocity you also double momentum but you quadruple energy. A crossbow bolt (50g, 80m/s) might have the same momentum as a rifle bullet(5g, 800m/s) but the bullet has 10 times the energy and thus penetration/damage potential.

A high impulse(momentum) eventually knocks over but penetrating/damaging armour and tissue is done by energy.

[eux0r]

ok, wait, im having trouble understanding everything you want to say. also, after reading what i wrote again, i realize its kinda sounding strange. what i mean is _not_ to approximate the equation F=m*a with F=m*v _but_ to estimate the damaging potential of a projectile by using its impulse p=m*v.
next: when a bolt is in the air, then youre right, there is no force. but while its in the process of hitting its target, a force is being applied, on both the
bolt as well as the location on the target, where it strikes. the bolt is applying force for a very limited time, yes, but its a finite time which does not equal zero. when swinging a weapon in close combat you can stay in contact with the target much longer, but that does not mean its in any way different from a projectile in regards to applying forces.

I think the momentum is not good to describe the damage potential. If look at a projectile with a speed v and a mass m you can calculate both the momentum p=m*v and the kinetic energy E=1/2*m*v^2. So if you double the mass, you double energy and momentum but if you double velocity you also double momentum but you quadruple energy. A crossbow bolt (50g, 80m/s) might have the same momentum as a rifle bullet(5g, 800m/s) but the bullet has 10 times the energy and thus penetration/damage potential.

A high impulse(momentum) eventually knocks over but penetrating/damaging armour and tissue is done by energy.

i know its a crappy approximation, thats what is said myself. its not that i think its good, its just that since kohaku was convinced that one was being used, i think he probably has some reason for it. so i am only trying to find the reasoning behind using that formula.

I'm fairly sure that the game currently works on a "Force = Mass x Acceleration Velocity" formula.

also, one should not underestimate the damage potential of crossbows. even the non-modern ones were sometimes capable of penetrating steel plates, which even some modern firearms cant. so having more kinetic energy does not necessarily mean dealing more damage, since, its the forces involved which actually do anything. its too much about other factors to say which property is best to describe the effectiveness of a projectile before it hits its target. in your example, should the bolt and the bullet be decelerated in the same time, they are capable of applying the same force, but its the question to where and how those forces apply to determine which one is more harmful.

[Moddan]

No, the only cases where I could follow your thought is when a bullet is deflected(flat impact angle) or wents right through the target without transfering all energy. If both the bolt and the bullet gets stuck in the victim, they transfer their momentum and energy. While the momentum or knockback is about the same, the bullet can do a lot more damage(10 times the energy). Of course it gets complicated with wound channels and stuff, but for overcoming something like a steel plate armour, the bullet wins by a mile. Energy is important there for getting the steel out of the way.

The rifle bullet outperforms the bolt by far in terms of steel penetration. 60 year old 7.62x51mm standard Nato penetrates (source) a standard NATO 3.45 mm steel plate up to 620m. Something my example crossbow would have troubles with at point blank I am sure. Historical plate armours had a thickness of 2-3mm at most if I remember correctly.

[Mel_Vixen]

Crossbows just dont shoot only bolts. The big military versions (relativly late) x-bows shot stone, ceramics and lead bullets because a standart bolt would shatter on the impact of the senew. These bows hadsometimes more kinetic power then todays handheld guns (by that i mean plain 9mm stuff, you guncrazy dorfs) therefore you had whinches and mechanics to get themloaded.

A riffle is something different thought not to mention that a riffles bullet is bellshaped which gives it a point.

[eux0r]

its not only when deflecting and penetrating right through the target but also when the projectile and the target deform. yes, energy is important, but its also about how it is transformed. a bullet with 10 times the energy of a bolt, may not penetrate a steel plate the bolt can penetrate, when the bullet has a round tip and is made of soft lead while the bolt has a sharp tungsten tip.

also, please note the words i chose:

even the non-modern ones were sometimes capable of penetrating steel plates, which even some modern firearms cant.

"sometimes" and "some", dont go comparing a 7.62mm bullet with wooden crossbow bolts on me... think more of an expanding 9mm bullet against a steel tipped arbalest bolt. in medieval times crossbows were even banned by the church from use against christians, because of their penetration power against armour-clad knights(it was still ok to shoot all those pagans though and in war against christians, the people on the battlefield didnt really care about some weapon-bans).

[Moddan]

My argument was that kinetic energy is responsible for target damage and not momentum. I think a FMJ 9mm(8g, 360m/s, 3.2 times the bolt energy) would still penetrate plate armour at close distance - and better than my crossbow. A hollow point bullet might desintegrate and spend its energy on that as well on the bullet fragment's kinetic energy. But if the FMJ bullet manages to transfer a good part of its energy to the target, it will perform better in overcoming the armour than the bolt in my opinion.

[Mr S]

Tangentially related, Mythbusters have done numerous material tests on various projectiles, if you'd like to see video of soft science.

OR you could read some texts on ballistics theory, material sciences, battle field medicine, etc. and get the hard science.

[eux0r]

My argument was that kinetic energy is responsible for target damage and not momentum. I think a FMJ 9mm(8g, 360m/s, 3.2 times the bolt energy) would still penetrate plate armour at close distance - and better than my crossbow. A hollow point bullet might desintegrate and spend its energy on that as well on the bullet fragment's kinetic energy. But if the FMJ bullet manages to transfer a good part of its energy to the target, it will perform better in overcoming the armour than the bolt in my opinion.

you posses a crossbow, and i assume you live in the US? so getting a firearm too, even when just borrowing, shouldnt be a problem? maybe you want to do some !science! on that matter, so we can have clear results?

Tangentially related, Mythbusters have done numerous material tests on various projectiles, if you'd like to see video of soft science.

OR you could read some texts on ballistics theory, material sciences, battle field medicine, etc. and get the hard science.

gotta watch that mythbusters stuff later on, since i already know about the billistics theory and material sciences stuff(which is why i am talking about material-stress all the time)

[Elone]

Not to ruin your fun here, but remember that this is an official thread, made by the admin, for something else XD I admit that I derailed too, but I used spoilers and I did not write blocks of text while quoting blocks of text which quote a text block =O ! And the topic of discussion is slowly drifting to modern physics and modern firearms.

[Gaspa Craftdreams]

Well this is a very unsettling thought but I thought I might share it for those who care.

Is there a contingency plan for when Toady is somehow unable to continue working on Dwarf fortress anymore?  I assume that Toady has backup drives and backup drives for those backup drives, but what happens if he somehow gets a crippling illness or has a severe case of sudden death syndrome?  What if both brothers are unexpectedly killed in something as mundane as a car accident?  Who would be left to continue their work?

[Rose]

Well this is a very unsettling thought but I thought I might share it for those who care.

Is there a contingency plan for when Toady is somehow unable to continue working on Dwarf fortress anymore?  I assume that Toady has backup drives and backup drives for those backup drives, but what happens if he somehow gets a crippling illness or has a severe case of sudden death syndrome?  What if both brothers are unexpectedly killed in something as mundane as a car accident?  Who would be left to continue their work?

I forget where it was stated, but I remember it being said that captaintastic and footkerchief both have portions of the source, that they will release if toady dies a natural death, and destroy if they suspect any kind of fowl play.

[PTTG??]

...Huh. Anyone know where I can sell forty poisonous snakes? I just realized I won't be needing them.

[Rose]

I think I know a guy. said something about a plane.

[Footkerchief]

Well this is a very unsettling thought but I thought I might share it for those who care.

Is there a contingency plan for when Toady is somehow unable to continue working on Dwarf fortress anymore?  I assume that Toady has backup drives and backup drives for those backup drives, but what happens if he somehow gets a crippling illness or has a severe case of sudden death syndrome?  What if both brothers are unexpectedly killed in something as mundane as a car accident?  Who would be left to continue their work?

I forget where it was stated, but I remember it being said that captaintastic and footkerchief both have portions of the source, that they will release if toady dies a natural death, and destroy if they suspect any kind of fowl play.

I can't speak for the Capn, but I don't have any source code.

Toady discussed releasing the source in case of his own death.  I don't think it's been discussed what would happen if both brothers met an untimely end:

Yeah, we've mentioned my untimely demise before, most recently because this town has lots of drunks and meth and some of the stupidest ass people that yell at you from vehicles as you might ever encounter (despite warnings from well-meaning people with misgivings about Texas, nothing ever happened down there, whereas up here in Silverdale I've been yelled at or had crap thrown at me or whatever no fewer than fifteen times while shopping, etc., even though I walked more down there), and the idea was to release everything.  I should amend that though -- if there are suspicions of foul play, and the preponderance of the evidence suggests that the death was related to getting the source released, then, well, no source then.  Yes, you will be punished for the wrongdoings of others, so pray for my safety!  No killing for the source!

[eux0r]

Not to ruin your fun here, but remember that this is an official thread, made by the admin, for something else XD I admit that I derailed too, but I used spoilers and I did not write blocks of text while quoting blocks of text which quote a text block =O ! And the topic of discussion is slowly drifting to modern physics and modern firearms.

yeah, i guess youre right, its time to drop it, even thought modern physics in principle are the same as those of ye olden times, just that nobody knew about them