Hey guys!
Was talking to a friend of mine today and well I was wondering why does the longbow do more damage then a shortbow?
I mean I have an idea: That it shoots farther, but what if you shoot from the same distance why would it do more damage?
Thanks ahead of time Everyone!
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Hey guys!
Was talking to a friend of mine today and well I was wondering why does the longbow do more damage then a shortbow?
I mean I have an idea: That it shoots farther, but what if you shoot from the same distance why would it do more damage?
Thanks ahead of time Everyone!
Way more pounds of force per square inch over the shortbow accelerates the arrow from zero to 127.5(m/s/s)/v-m. At Tv, gravity further accelerates the arrow at 9.6m/s. Under normal conditions with no force other than gravity acting upon the arrow it will reach a Tv (defined as impact with the target) at more than 2000 times the force at initial acceleration--sending it very neatly through a quarter inch of plate, 1/8 inch of leather underpadding, 1 inch of cotton-wool blend padding, four-to six inches of tense flesh, three inches of healthy bone; another six-ten inches of tense flesh, another 1 inch of cotton-wool padding, another 1/8th inch of leather underpadding; finally embedding the head in the leather of a cavalryman's saddle...and that's assuming normal range, a level ground. If fired from an altitude higher than the target, we get some more velocity and greater penetration!
Yeah, basically what he said. Put differently, the longbow pushes the arrow farther because it pushes harder. The basic principle is that Force = Mass*Acceleration. For the arrow to travel farther before crashing into the earth, it must have a greater horizontal component to its velocity, which makes for a greater change in velocity on impact and thus a greater amount of force exerted on you. As Andrew Turner notes, if you're able to get higher ground (and thus put gravitational acceleration to work for you as well) your total velocity will be greater as well.
If (as I've heard -- I don't know from personal experience) the arrows for longbows are larger than are the arrows for shortbows, that increases the mass as well, thus increasing the difference in force yet again.
yep; the only thing I can add is draw length; a shortbow has less draw length due to the shorter arrows and shorter pull distance of perhaps 18 to 20" compared to a longbow pull of perhaps 27" or more for a greatbow; also the arrows can be heavier and use heavier tips. The increase draw length increases the amount of time the arrow is pushed so the accelleration curve is longer; I could write out the formula for you, but doubt you care, so add this consideration into the force of the bow due to materials and draw strength of various bow sizes and you can pretty much see why a longer bow has more impact.
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Was talking to a friend of mine today and well I was wondering why does the longbow do more damage then a shortbow?
Longer bows have longer pull lengths, which means they add energy to the arrows they shoot for a longer time, which means that for a given pull weight, the arrows from those bows have more energy. Stronger bows (Composite bows with STR modifiers) can be assumed to have greater pull weights, which also results in more energy in the arrow.
D&D assumes that arrow damage correlates in some systematic way with projectile energy**.
As noted above, a higher energy arrow will also (all else being equal*) shoot farther. The cause is the energy, not the distance.
* I'm explicitly neglecting issues of sectional density, arrow vibration, angle at launch, arrow mass, variable air resistance with velocity, and a host of other possible inequalities with that blithe statement.
** I'm not convinced that this is a solid assumption with subsonic projectiles, but it's not unreasonable on its face. Certainly, there is a lower limit below which the projectile will not meaningfully penetrate and an upper limit above which more penetration is largely irrelevant.
ps. If you find actual armor that is 1/4" thick, let me know. I've certainly never seen it in any museum, never seen any recreation of it, and never worn any such thing.
pps. Driving an arrow through anything but the very thinnest possible steel plate (far thinner than 1/4") with a bow is ridiculously improbable. The experiments have been done over and over again. (Nothing in the D&D model requires plate penetration, BTW.)
ppps. Sebastian and Saern should probably avert their eyes from this post.
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I remember a video from a hunter's education course I took a long, long time ago where they had a mirror sitting behind a large (probably 5 gallon) metal pail filled with sand.
A slug fired from a shotgun (I forget which gauge) is stopped by the sand. An arrow fired from what was described as a "typical native american bow) penetrated the bucket and busted the mirror on the other side. An arrow fired from a compound bow when through the bucket, through the mirror, and half way through the bale of hay behind it.
(a smattering of my own knowledge, but mostly from http://en.wikipedia.org/wiki/English_longbow follows:)
Now, to the discussion at hand, because of the increased draw distance, a longbow would naturally have to have a larger arrow than a shortbow, also, some English Longbows were said to have a draw strength of 175+ ft-lbs (modern hunting bows are in the 50-60 ft-lb range). I think the increased damage in DND is simply a nod to the fact that these bows fire heavier arrows (65-100 gram arrows, 3-4x heavier than modern arrows) at faster speeds (and thus can pentrate armor much more easily).
These bows and arrows are said to have "[…] in the war against the Welsh, one of the men of arms was struck by an arrow shot at him by a Welshman. It went right through his thigh, high up, where it was protected inside and outside the leg by his iron cuirasses, and then through the skirt of his leather tunic; next it penetrated that part of the saddle which is called the alva or seat; and finally it lodged in his horse, driving so deep that it killed the animal." The Welsh often used arrows that were designed to break apart chainmail and have enough force to cause a "gaping" hole by blowing the links apart.
A lot of power involved there. However, the bodkin arrows are said to have had difficulty penetrating steel plate, and only by firing a storm of arrows were they effective in finding the weak points in the armor.
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I have a Spanish cuisse which measures in at 6mm...just a hair under a quarter inch...
I'll take your word for that, of course. Is that piece purported to have been worn in period? Iron is 7.86 g/cc (steel varies, but is close to that), and I'd expect a cuisse to be around 700-800 cm^2. That would put that one piece of armor somewhere near 3.3 kg (7 lbs. or so). That might work for jousting plate, but for combat armor ... let's just say that I like steel a lot, but I wouldn't wear it.
Frankly, unless you're planning to try to stop bullets, even 2mm plate is really too thick to be usable. 2mm is certainly thick enough to stop all or nearly all bodkin-point arrows, even at close range and with a 90 degree angle of incidence (as the Royal Armouries has shown with actual testing).
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I have a Spanish cuisse which measures in at 6mm...just a hair under a quarter inch...I'll take your word for that, of course. Is that piece purported to have been worn in period? Iron is 7.86 g/cc (steel varies, but is close to that), and I'd expect a cuisse to be around 700-800 cm^2. That would put that one piece of armor somewhere near 3.3 kg (7 lbs. or so). That might work for jousting plate, but for combat armor ... let's just say that I like steel a lot, but I wouldn't wear it.
Frankly, unless you're planning to try to stop bullets, even 2mm plate is really too thick to be usable. 2mm is certainly thick enough to stop all or nearly all bodkin-point arrows, even at close range and with a 90 degree angle of incidence (as the Royal Armouries has shown with actual testing).
I am quite embarrassed...my wife laughed at me when I related this thread to her. She then proceded to my office, pulled out a ruler from my desk and measured one of the cuisse...at the thickest portion...about 3mm. :\
I don't quite know what was going through my head when I measured them this morning...
They're both reproductions I bought a few years ago in Williamsburg, VA, supposedly of a 15th Century Fuensaldana model.
well, also keep in mind that armor thickness is not uniform; well, at least they were not in the old days; armor was thicker in more critical areas and thinner in others; after the advent of gunpowder weapons became semi common; armor also got thicker until such a point as weapons became more powerful and the armor mass needed to stop a round became unwearable. Just my brain flea to jump around yer brain.
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I don't quite know what was going through my head when I measured them this morning...
They're both reproductions I bought a few years ago in Williamsburg, VA, supposedly of a 15th Century Fuensaldana model.
No worries. I was really skeptical of the thickness, but I've seen some absurd stuff made, so I was willing to believe. Thanks for letting me know about the mistake.
15th century (esp. late 15th century) puts it around the time when armors started to seriously thicken up to respond to firearms. Mobility is crucial on the battlefield and wearing armor is exhausting, so armor is usually made as light as practical. Firearms changed the definition of practical.
For melee weapons and most arrows, 1 - 1.5 mm is plenty (and the Royal Armouries' tests found that two layers of 1.25 mm plate would stop any longbow arrow). Plates of that thickness will dent fairly easily under impact, but dents can be bashed out easily enough (particularly if you have a servant to do the bashing).
BTW, I've found rigid leather armors (cuirboilli - leather boiled in paraffin) to be both heavier and more constricting than steel plates (also true of mail). Rigid plastic, though, works really well. 8-)
From my wife's experience in the criminology field at college: it doesn't. Arrows shear through kevlar.
Now, there's an alternate model that is meant to be knife resistant; that probably offers some protection.
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From experience: Kevlar is a 'life saver'...just not sure how well it would stand up to arrows... ;)
Sorry about the "experience", glad about the "life saver".
From my wife's experience in the criminology field at college: it doesn't. Arrows shear through kevlar.
I'd heard that knives cut kevlar fabric, so I'm not surprised about arrows. Barrel plastic*, now, might work pretty well, though I suspect it wouldn't help against bullets at all.
* Armor made from cut-up pieces (see this page, for instance) of chemical barrels is commonly used by SCA fighters who aren't much worried about authenticity. It's very light for its strength and durability. After trying to cut it with shears, I think it would stand up pretty well to blades. 8-\
ppps. Sebastian and Saern should probably avert their eyes from this post.
Grumble grumble.
Seriously, however, I do realize that there is a certain level of physics, some parts being more complex than others, that are completely unavoidable in the formulating of a rule for D&D (time it takes to fall X distance, why longbows do more damage {presuming that D&D's assumptions are correct}). Once formulated, however, we've enetered into the land of rules balance, simplicity, etc., which takes physics about as seriously as a Bond movie or Star Wars (because lasers really do look like that, totally!). Essentially, if it's possible to make a rules call without restorting to physcics, I'll always prefer that option. :)
Ahem... back to the thread at hand....