If a person and a gun were shrunk down to 4 inches and shot another normal-sized person, what would happen?

No way. it would be like sticking someone with a pin.

average bullet speed about 300m/s
average bullet weight... 100g?
kinetic energy = 1/2*m*v^2 = 9000j

reduce by factor of ten

speed = 30m/s
weight = 0.1g
kinetic energy = 0.045j

I think.

(forgot to divide by half in first equation, should be 4500j)

WOTS THAT IN LAY MANS TERMS?

http://www.mjsimpson.co.uk/reviews/Resources/dollma6.jpeg

damage is more about the bullet's velocity than size, though i guess shrinking the propellant would affect that

In other words bullet would have 1/100,000 as much energy.

sounds like a job for MYTHBUSTERS

and mookie if you had ever seen an episode of that show you would know that MASS is more important than SPEED since they consistently be shooting playing cards and wood splinters into the ballistics jello and never getting lethal results

robots in dis guys

(xpost to self) so we may assume it would penetrate 1/100,000 as far. Police handguns can penetrate 30cm of gelatin at 5 metres so yr tiny bullet would penetrate 0.0003cm.

Dudes it's not mass or speed it's kinetic energy.

Which is heavier, a ton of bricks or a ton of feathers?

speed = 30m/s
weight = 0.1g
kinetic energy = 0.045j

why would the bullet be slower?

Hmmm you seem to have a point there. Powder should apply same amount of force to bullet if they've both been reduced by the same amount.

shorter barrel length matters. why am i talking about this, i don't know anything

anyway they wouldn't bounce off, they'd deform against the skin and then fall off.

The small person would get arrested

xposts again, that would make the answer 4.5j, i.e. 1/1000 as much energy. Still probably not much more than a light tap.

... roughly equal to dropping a normal bullet from a height of 20 metres, if my calculations are not incorrect again.

http://inspireaction.mindandmedia.com/wp-content/uploads/2007/07/lets-get-small.jpg

what if the original gun was one of these

http://www.navy.mil/navydata/ships/battleships/newjersey/nj-1984beirut.jpg

5 metres, sorry.

xposts.

God I'm tragic.

good thread.

I don't see why the muzzle velocity of the tiny bullet would be any less, though the atmosphere might slow it down more than a larger projectile.

I'm pretty sure the muzzle velocity would be significantly less, myself.

If everything were in proportion, the time the bullet would take to cover its own length would remain about the same, but with a shorter length, the speed would diminish.

everything is cuter when smaller - fact.
so if a wee person shot a normal one with a wee gun the bullet would make an adorable squeek sound as it indented the persons' leg (i would imagine a 4" person would about that level) and everyone in the room would go "awwwww - you're so kewt wif your widdle gun, aren't you!?"
it's science.

If everything were in proportion, the time the bullet would take to cover its own length would remain about the same

if in "everything" you include speed then yes by definition. Otherwise... you have to look at what is supplying the motive force and how you assume it would "realistically" behave when scaled down, an inherently unrealistic scenario.

the drugs would eventually wear off

Shoot for the eyes, little guy!

so with less gunpowder, the force would go down exponentially rather than proportionally?

i was going to suggest doing this with a nuclear bomb, but there's a minimum size at which the nuke will still work as violently as ever, below which it won't work at all.

xpost What? Well yes, it would reduce by the cube of the scaling factor (assuming gunpowder force is directly proportional to amount). But more importantly the bullet is reduced in size too. So the gunpowder has less force but the bullet has less weight - so the velocity is the same.

But even that might be oversimplifying.

Whenever I think about someone being shrunk, I always wonder whether that person would even be able to breathe normal air.

probably lung surface area would be too small.

Lots of 4" animals can breath normal air, I've seen them.

Also 4 inches isn't that small for a gun, but 4 inch person would probably not be able to fire it.

xpost, but do they shrink the cells? the atoms? Would the shrunken person even be compatible with our universe????

Everyone on this thread is totally stoned, yes?

Haha, no. I've actually thought about this quite a bit!

haha, me too, Spencer! like, I wonder whether really a really really tiny person would be able to see microscopic things (cells? molecules? atoms???). but then I start to worry about the photons being too big and fucking everything up, so that you'd just kind of see a really blurry low-res enlargement of what a normal person would see.

woah

migraine

http://www.youtube.com/watch?v=KIq3JkoABYM

^^^ world's smallest working gun. Looks just about right for 4" Leeee

88alex69 (4 minutes ago)
it is a 2.34mm bullet weighing 1.9 grams with 1.9 ft-lbf of bullet energy

lol u all so high

the problem is that the concept of "shrinking" has no meaning in terms of conventional physics.

iow yeah lolz you high

http://img98.imageshack.us/img98/708/vrg45wq3.jpg

sounds like a job for MYTHBUSTERS

no wai, god that's boring. They have real jobs, you know. Adam and Jamie are finding out for all of us what happens when you put enough dynamite in the trousers of a ballistic dummy to blast a new rail line through the Sierras, and Kari and Grant are at last getting to the bottom of whether vodka makes you drunk.

1.9ft-lb = about 2.5j - close enough to my 4.5 estimate.

ft-lb. I hate that unit. Hurry up and metricate.

average bullet weight... 100g?

no, 9mm weighs around 7.5 grams.

why a factor of 10? Average height of 5'10", reduced to 4" is a 1/17.5 reduction.

a 9mm bullet would be reduced to just over half a millimeter in diameter, and weigh somewhere around 1.4 milligrams, or about as much as 14 grains of salt.

so even assuming velocity would remain the same at 300m/s, which I doubt, you're looking at 0.07 joules which is approximately nothing. Bring it.

This reminds me of http://en.wikipedia.org/wiki/Battleground_(short_story).

Oh dude: http://www.youtube.com/watch?v=uZ62_HHTOOM

why are we assuming the mass goes down? we're SHRINKING the person, not building a microperson.

from a chemistry perspective, the extra-dense gunpowder reaction might be even more powerful since it will have a much higher surface:volume ratio

and the same mass striking flesh w/ an even smaller cross-section is going to have more penetration power, not less.

no, 9mm weighs around 7.5 grams.

ok i thought 100 was far too high but i got it from hurried googling.

why a factor of 10?

SIMPLICITY

It this was all reversed and everything were 4 times bigger it would cause major damage so couldn’t we assume that the tiny version would just cause a little damage? Oh hell I don’t know. I will think about this later when I AM high

I imagine it would be something like this
Youtube Six Shooter

A person shrinking shrinks in all 3 dimensions (height, width, and depth), so it's really a 1/(17.5**3) factor.

The shrunken midget gunman could not walk or lift his hyper-dense arms to fire the gun.

I bet he would try to use it to fend off the giant ant trying to eat the giant oreo he was standing in, and fail. Then he would get caught in a Cheerio floating in milk and unsuccessfully use the gun as a propulsion method. Then he would shoot himself right in his teeny noggin.

when i was a kid i would wish for shrinking ability so that i could use small pools of water to swim in

supposing it was shrunken arnold schwarzenegger?

Arnold is 6'2". Assuming no decrease in mass, at 4" tall he would be 6331.625 times his normal density.

Since this is all pie-in-the-sci-fi, I'll suggest that if the mini-man loses no mass in the shrinking process and his relative strength is the same, then he must exist in a compressed dimensional bubble, and that if he shot at you from within this bubble, then the bullet would reexpand to normal dimensions upon transitioning out of the bubble, and there would be no difference in its effect.

You're looking at the gunman through binoculars backwards, basically.

I think you've just described an episode of Harvey Birdman

The four inch person wouldn't be able to aim the four inch gun properly, so they'd probably miss the normal sized person. The recoil would probably injure the four inch person quite badly.

at what range is the tiny person shooting the normal person ?

Has anyone read The Indian in the Cupboard? I can't quite remember the detail but I think the kid in it does suffer the effects of tiny revolvers and/or bows and arrows, and I think it's quite uncomfortable for him. I assume Ms Reid Banks did scientific research on the matter.

I would assume not. Hey ya know what happens when you ASSUME...

An exciting chart of handgun bullet weight, muzzle velocity, kinetic energy, gelatin penetration, and efficiency at killing goats:
http://www.chuckhawks.com/handgun_power_chart.htm