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[SealyStar]

I was at the store and saw big packs of AAA batteries, all lined up like ammo clips. That gave me an idea for a "battery gun" which would drain batteries and then use the energy to launch them railgun-style. Assuming 100% energy efficiency, I applied conservation of energy with energy and mass values from teh internets and (apparently) my second-law-defiant battery gun could have a muzzle velocity of 900-some meters per second. Even when you take nasssty entropy into account, the numbers seem absurdly high for, you know, AAA batteries. Am I doing something wrong?

[MetalSlimeHunt]

I was at the store and saw big packs of AAA batteries, all lined up like ammo clips. That gave me an idea for a "battery gun" which would drain batteries and then use the energy to launch them railgun-style. Assuming 100% energy efficiency, I applied conservation of energy with energy and mass values from teh internets and (apparently) my second-law-defiant battery gun could have a muzzle velocity of 900-some meters per second. Even when you take nasssty entropy into account, the numbers seem absurdly high for, you know, AAA batteries. Am I doing something wrong?

*Cough*

[SealyStar]

I was at the store and saw big packs of AAA batteries, all lined up like ammo clips. That gave me an idea for a "battery gun" which would drain batteries and then use the energy to launch them railgun-style. Assuming 100% energy efficiency, I applied conservation of energy with energy and mass values from teh internets and (apparently) my second-law-defiant battery gun could have a muzzle velocity of 900-some meters per second. Even when you take nasssty entropy into account, the numbers seem absurdly high for, you know, AAA batteries. Am I doing something wrong?

*Cough*

So obviously I just need to get it to 50%-ish efficiency somehow. Eeexcellent. Know any easily abductable electric engineers?

[tahujdt]

I was at the store and saw big packs of AAA batteries, all lined up like ammo clips. That gave me an idea for a "battery gun" which would drain batteries and then use the energy to launch them railgun-style. Assuming 100% energy efficiency, I applied conservation of energy with energy and mass values from teh internets and (apparently) my second-law-defiant battery gun could have a muzzle velocity of 900-some meters per second. Even when you take nasssty entropy into account, the numbers seem absurdly high for, you know, AAA batteries. Am I doing something wrong?

*Cough*

So obviously I just need to get it to 50%-ish efficiency somehow. Eeexcellent. Know any easily abductable electric engineers?

Depends. Can you be in downtown KCK at approximately 2:41 tomorrow? I'll have one ready for pickup.

[LordSlowpoke]

you can easily increase the efficiency of your coilgun by not making it a pure coilgun. coils are more efficient when your projectile already has gained some speed, i thought of utilizing something like a gas compressor to build up loadse pressure and then fire in bursts or something akin to that idea

still they're quite painful to utilize - it's either making them hella heavy/outright stationary (WHEN WILL PEOPLE GET THEIR SHIT TOGETHER AND MAKE BETTER BASIC ELECTRICAL DEVICES FUCK) or limiting a lot of things about the design

Surprisingly, my mum (A rather devout non-denominational liberal Christian) has told me recently that she's always struggled with the idea that God is supposed to be more powerful than Satan, and is supposed to be totally good, but hasn't gotten rid of Satan.

* LordSlowpoke flips open notes

okay i've got this

god creates humans, right? so they're imperfect, because we're created in his image and shit, he's not creating other gods so he's not creating other perfect beings (why he would want to create other gods in the first place i do not know)

so yeah you've got this stuff like good and evil and there's a whole load of shit to be said about the natural alignment of a human being but let's assume it to be chaotic good to simplify, and when humans lapse into evil it's always satan manipulating their shit and god allows that to happen because if he didn't everything would be stagnant and if everything would be stagnant people would just sit on their asses and do nothing thinking they've achieved perfection but nope you've got lucifer wrecking that shit so humans have to get off said collective ass and rebuild everything

but now that they already built it once they know the previous order's had a bunch of flaws in it and fix said flaws then go back to sitting on their asses until the order's fucked up again

that's how humans become more perfect

i'm not even christian go eat a bag of salt vOv

[MonkeyHead]

You just have overlooked something important... there is no way a single AAA, let alone a bunch of AAA's will run any kind of useful dangerous coilgun, unless you have a LOT of them, and a VERY large capactior array you dont mind taking absolutley ages to charge up. Add in the fact that coilguns dont often get into the double figures for efficiency... yea, something has gone wrong there.

The few coilguns I have built used 9 or 12 V cells or DC power supplies, multiple 1F capacitors, and thousands of coils, occasionally activating in sequence, and I struggled to get beyond around 40 to 50 m/s without serious heat problems.

[Graknorke]

I was at the store and saw big packs of AAA batteries, all lined up like ammo clips. That gave me an idea for a "battery gun" which would drain batteries and then use the energy to launch them railgun-style. Assuming 100% energy efficiency, I applied conservation of energy with energy and mass values from teh internets and (apparently) my second-law-defiant battery gun could have a muzzle velocity of 900-some meters per second. Even when you take nasssty entropy into account, the numbers seem absurdly high for, you know, AAA batteries. Am I doing something wrong?

*Cough*

That is not a railgun. Am I missing something?

[MetalSlimeHunt]

No, it's not a railgun, it's a coilgun.

[SealyStar]

You just have overlooked something important... there is no way a single AAA, let alone a bunch of AAA's will run any kind of useful dangerous coilgun, unless you have a LOT of them, and a VERY large capactior array you dont mind taking absolutley ages to charge up. Add in the fact that coilguns dont often get into the double figures for efficiency... yea, something has gone wrong there.

My sources may very well be completely wrong, but they said a AAA has ~5000 J worth of energy and a mass of 10-12 g. Obviously you're right about the sorts of capacitors needed to store that much energy and release it all at once, though, to say nothing of the time to drain that much energy from the battery.

We were already sort of discussing efficiency. Yeah, that's the big problem, which is best left to my soon-to-be-formed electrical engineer slave army.

All in all, the basic concept is more interesting, if useless - projectiles that come with their own power supply, like regular bullets but with electricity.

[lemon10]

You just have overlooked something important... there is no way a single AAA, let alone a bunch of AAA's will run any kind of useful dangerous coilgun, unless you have a LOT of them, and a VERY large capactior array you dont mind taking absolutley ages to charge up. Add in the fact that coilguns dont often get into the double figures for efficiency... yea, something has gone wrong there.

My sources may very well be completely wrong, but they said a AAA has ~5000 J worth of energy and a mass of 10-12 g. Obviously you're right about the sorts of capacitors needed to store that much energy and release it all at once, though, to say nothing of the time to drain that much energy from the battery.

We were already sort of discussing efficiency. Yeah, that's the big problem, which is best left to my soon-to-be-formed electrical engineer slave army.

All in all, the basic concept is more interesting, if useless - projectiles that come with their own power supply, like regular bullets but with electricity.

It sounds like you are draining the battery instantly to power the gun, which if it was indeed possible, seems like it would get crazy velocity, because you get quite a lot of of power out of a regular battery.
It takes hours at best (?) to drain one though, so no way that would work in practice.
EDIT: Derp, didn't read that post at all apparently.
But yeah, the numbers do sound fine, you get tons of energy from one battery, but as they take hours at fastest to drain, you never see a surge like that in real life.

[MonkeyHead]

The obvious solution that leaps out to me would be not to fire a cell (not great energy stored, nor current delivered), but to fire a large pre-charged capacitor which dumps its energy into the firing system...

I may just have to try this.

[BlackFlyme]

The person beside me asked what a giraffe was today in the middle of a test.

[HFS]

I think I married a part of my subconscious last night. Wat do.

Spoiler (click to show/hide)

A recurring dream character, to be precise.

[MagmaMcFry]

Best wishes, and may you live a long and joyous life together.

[SealyStar]

Ugh. I feel for you. Subconscious divorce court is always messy. Hope you don't have any dream kids. Also, you now must pay half your income as subconscious alimony, meaning half your money literally disappears into your brain. Oh, but conservation of mass-energy applies, so your brain gets superpowered by the extra electrical energy in it. It's a tradeoff.