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/sci/ - Science, Technology, Engineering, and Mathematics

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Movies & TV 24/7 via Channel7: Web Player, .m3u file. Music via Radio7: Web Player, .m3u file.

WebM is now available sitewide! Please check this thread for more info.

Anonymous 14/11/22(Sat)00:15 No. 15973 ID: 7fa0bd [Reply]

File 141661174892.jpg - (104.70KB , 640x360 , portal dalek.jpg )


2 posts omitted. Click Reply to view.
Anonymous 14/11/22(Sat)23:44 No. 15980 ID: 5d199c

To me they look like portable life-support/coffins. Picture some 112 year old codger wrinkled up inside one guiding it round akin to a spaz marin dreadnought. That way the expired can enjoy 'normal' life well past their expectancy.

Anonymous 14/11/24(Mon)05:42 No. 15983 ID: c4e26c

So like, a Dalek then.

Anonymous 14/11/26(Wed)20:43 No. 15988 ID: ab4c09


lol ftw.

America VS the metric system Anonymous 11/11/28(Mon)22:57 No. 12847 ID: 2dcfee [Reply] [First 100 posts] [Last 50 posts]

File 132251746298.jpg - (33.63KB , 400x308 , FAT AMERICAN.jpg )

It’s hard to find comedy gold like this, however this is priceless


Apparently a true American tries to show the failures of this evil satanic scientific metric system and fails horribly.

Best parts:

1) Arguing that centimeters are not part of the metric system!
>"Centimeters, while in common usage, are NOT officially recognized metric units"

2) Actually trying to measure something using 0.1 mm obviously not understanding that this precision is not actually possible with human hands.
>"In metric notation this would be 1219.2mm by 2438.4mm."

126 posts and 10 images omitted. Click Reply to view.
Anonymous 14/11/22(Sat)16:27 No. 15979 ID: 287212


Are you saying that 3 meters = 9 feet?

Anonymous 14/11/23(Sun)09:48 No. 15981 ID: d2ef46

Why does this thread still exist. Every time I visit this board, it's on the front page, hosting a series of one retarded comment after another.

Just learn both. You assholes sound like those people who think everyone in the world should only speak one language. It's fucking stupid. Could a mod please lock this thread?

Anonymous 14/11/24(Mon)06:20 No. 15985 ID: c4e26c

The construction industry was the source of the backlash when the U.S. tried converting to metric in the 60s. Muh Two Bah Fer!!!

Well, a 2x4 was a convenient size, a 2x6 or 10 was as well. No one wanted to complicate matters. Forward to today, and lumber mfg's have repeatedly shaved so much material off their finished products, those numbers are nominal only. A 2x4 is actually roughly a 1.5x3.5, precision & tolerances depending on mfg's QC.

So these toothless bearded fags are already using screwey numbers... Running an entire project with tens of thousands of calculations made based on this idiocy, and all the fucking trouble it causes when the new guy builds shit based on the wrong sizes, they can live with, but calling a 2x4 what it actually is, a 4x9, 4cmx9cm, BLOWS THEIR FUCKING MINDS.

Further proof Europe sent its most retarded and stubborn inbred hicks to populate this country.

Anonymous 14/10/19(Sun)11:15 No. 15940 ID: e9758b [Reply]

File 141371012595.jpg - (61.35KB , 700x479 , 17775_lores.jpg )

How much money you reckon ebola raised for in the name of science? thanks little fella!

3 posts and 1 image omitted. Click Reply to view.
Woo. 14/11/01(Sat)16:07 No. 15959 ID: 2429da

File 141485445093.jpg - (95.39KB , 945x552 , ebola-body-bag.jpg )

Thank you, little buddies! :D

Anonymous 14/11/18(Tue)05:41 No. 15971 ID: a4fae5

>that one laughing nigger in the middle

Anonymous 14/12/26(Fri)12:41 No. 16011 ID: 243dac

I don't see anyone laughing because none of them are.

Parabolas in autodesk inventor Anonymous 14/11/04(Tue)17:45 No. 15963 ID: b2989d [Reply]

File 141511955922.png - (2.77KB , 197x256 , parabola.png )

I need to create a parabola in autodesk inventor for a school assignment, and the parabola needs to be shaped like the bottom of a circle (kind of like a lid) what do?

Anonymous 14/11/08(Sat)09:40 No. 15965 ID: 789203

>the parabola needs to be shaped like the bottom of a circle
Well, that's not a parabola then, is it? It's an arc.
arc(x, h, v) = (v / h) * sqrt(h^2 - x^2)
h being the radius of the horizontal elliptical axis, and v the same of the vertical one.

Anonymous 14/10/12(Sun)19:00 No. 15929 ID: b20a90 [Reply]

File 141313325435.png - (193.71KB , 450x450 , BT clients.png )

Hello /sci/!

Does anyone please know of a program that can analyze torrents? What I want it to do is to create a printout of all the files in the torrent. I also want to make comparisions of torrents; to see if two torrents have files with the same name and/or the same hash value.

Anonymous 14/10/16(Thu)11:00 No. 15936 ID: 789203

Yes, dumptorrent.

Hashes are computed per-block, not per-file. Meaning, the hashes a torrent contains will depend not just on its particular contents, but also the particular order in which they appear, and the block size that was used. It's very unlikely that two distinct torrents containing the same file will also share any hashes, even if the block sizes are the same. It's even less likely if the file in question is smaller than twice the block size.

Let n be the absolute offset of the file on the torrent A (given by the sum of all the file sizes that came before), and let m be the same on B, if file_size >= block_size * 2 and n is congruent to m modulo block_size, then there will be at least one duplicate hash between the two torrents. For randomly constructed torrents (a reasonable situation) with a random file_size the probability of the congruency condition being met is of 1/block_size. So for block_size = 4 MiB (a common block size), the probability is lower than four million to 1.

Anonymous 14/10/07(Tue)08:26 No. 15918 ID: 1b02b6 [Reply]

File 141266316925.png - (44.05KB , 993x834 , dfgdfgdfg.png )

2 questions. In photo,

Exhibit 1: A point charge q exerts its electric field over a spherical body. Along the flux lines diverging "radially" away from point charge, there exists 2 points at opposite ends of sphere's surface area (along diameter). The electric field, E, in accordance with Coulomb's law, is stronger towards the charge than away from it, the vector lengths of E indicating this ever dying weakness, and vectors, dA, normal to the area.

Told: That the total electric field on the body is zero, because the cross product of the electric field on both points are "equal" but opposite, cancelling each other out. This applies to all points along surface area of the sphere.

Question: What is wrong in my photo? It seems that they have completely forgotten about Coulomb's law, in that the closer you are to a body, the stronger the electric field. If the point charge was negative, I imagine the electric field vectors to be a lot larger along the sphere's hemisphere closest to the point charge, and smaller on the other hemisphere. Wouldn't all but the tiny difference between the electric field strengths remain after cancellation? Shouldn't the total electric field be in slight favour of the negative charge's force?


Exhibit 2: a. A point, p, inside charged sphere has an electric field, E, of zero.
b. A point, p, exists in the sphere of a charged similar body comprising a sphere with an attached appendage that loops around half the sphere, with same electric field as E in exhibit 2a.

Told: That in all closed surfaces, the net electric field, E, at any point in the closed system is zero.

Message too long. Click here to view the full text.

Anonymous 14/10/07(Tue)09:10 No. 15921 ID: 1b02b6

Also, why are the charges along the surface? Is it just easier to think that way after summing all the negligible point charges together?

Anonymous 14/10/10(Fri)03:15 No. 15926 ID: 789203

1. I don't see how the field strengths on the surface could possibly have opposite directions unless the point charge is inside the sphere.

2. I agree with you, it seems counter-intuitive. I could easily construct a closed fractal shape that has infinite surface area on one side of the charge and is nearly spherical on the other. I'm not in physics, so I don't know what to tell you. See if this link helps:

Anonymous 14/10/10(Fri)19:00 No. 15928 ID: 1b02b6

I worded it poorly. E isn't opposite on both ends, dA is (normal to the surface on opposite ends). I was just trying to say that the field dies off the farther you are away from charge.

Meteorite Anonymous 14/08/18(Mon)20:37 No. 15827 ID: 040c46 [Reply]

File 140838707141.jpg - (104.25KB , 960x741 , Lunar Meteorite.jpg )

Kickstarter campaign to purchase Lunar Meteorite


Anonymous 14/09/19(Fri)15:01 No. 15879 ID: c4882d


Anonymous 14/09/20(Sat)15:50 No. 15886 ID: 15121f

You can grab your plain ol' honest-to-goodness meteorites from your gutter using a strong magnet. You'll get little chips that have bounced off your roof and collected there.

I thought I found a sizable meteor in my backyard, turns out it was industrial waste, slag, probably from WWII when my area was involved in war production and waste of this kind would be common.
It's an easy material to confuse for spacerock :)

Anonymous 14/09/08(Mon)10:07 No. 15872 ID: 84146f [Reply]

File 141016364114.jpg - (21.14KB , 521x161 , slui.jpg )

I need a product key activator for Windows 7 Ultimate SP1 ASAP. I tried activating it manually, but I receive this error message.

sage Dumb_Nigger 14/09/08(Mon)11:24 No. 15873 ID: b2bc2a

try google, faggot

Anonymous 14/09/16(Tue)14:44 No. 15876 ID: a29f36

Buy a real Windows 7 Ult key faggot

Anonymous 14/04/24(Thu)21:56 No. 15638 ID: cf7d56 [Reply]

File 139836940417.jpg - (32.02KB , 599x399 , image.jpg )

Faggotry is hormonal imbalance. It has to be. What else could it be besides environmental trauma?

22 posts omitted. Click Reply to view.
Anonymous 14/09/08(Mon)08:10 No. 15871 ID: 789203

>For example, being intelligent and/or social on its own doesn't provide much advantages as to being able to adapt to an unstable environment. Going down the list of most intelligent animals (excepting for the moment humans) is like taking a trip down the endangered species list.
Well, being smart isn't going to give you many advantages if you're going up against something smarter and more powerful than yourself. You can't outthink a bulldozer tearing through your home, or a gun shooting you in the face.
Being smart can help you figure out safer ways to get food. We devote over 1/5 of our energy expenditure to brain upkeep. Compare to around 1/20 for most other vertebrates. Having such large brains would put us at a significant disadvantage if they weren't able to compensate by providing more food and generally being better able to the body safe.

>Meanwhile, species like ants and bacteria that don't even have brains as we think of them thrive in every environment on Earth.
Just imagine how terrifying they'd be if they were smarter than us!

>The only reason human intelligence and cooperative power has provided an evolutionary edge is because it (after a few hundred-thousand years of doing nothing in particular) suddenly and exponentially enabled them to alter the environment to suit their needs. However, the same technology that gives humans long, (re)productive lives as medical care, perfect food, and air conditioning has also lead to global warming, which might be the thing that kills us all.
And? If that was our ultimate fate, it would just show that evolution is a sub-optimal algorithm, not that intelligence doesn't make sense evolutionarily.

Anonymous 14/09/10(Wed)03:54 No. 15874 ID: 00718f

>hormonal imbalance
I believe not in full grown people but in the womb enough testosterone was present for Y chromosomes etc but not enough to fully convert the brain leaving a more feminine physios

Matchbox Prince 14/09/11(Thu)10:04 No. 15875 ID: 2f260d


It's a myth that homosexuals have less testosterone; they actually tend to have more. Also, while the brains of homosexual men work more like heterosexual women in certain ways when looked at with PET or fMRI scans, the statistical difference is so insignificant (differences between individuals are far larger than the differences between the groups) that it's really irrelevant. Any association of homosexual men with feminine traits is culturally generated and exclusive to the modern, Western world.

Anonymous 14/09/05(Fri)02:34 No. 15861 ID: 9db7e9 [Reply]

File 140987727820.jpg - (233.09KB , 1240x1754 , 981.jpg )

I plan on doing a reductive amination (ketone + nitromethane) in the next few weeks, using Al + Ga metals.
Does anyone have any useful tips on this reaction?
(Reference: "Reductions in Organic Chemistry", Milos Hudlicky, Prof. Chem., Virginia Polytech. + state university).

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