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File: lenny.jpg (127 KB, 1920x1080)
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brainlet here

is the nuclear fusion in the sun a direct conversion of mass to energy or is it some percentage and if so what percentage.
11 replies and 2 images omitted. Click here to view.
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>>9679207
Fusion happens either with high pressure or with high temperature.
The sun gets by with 20 million degrees because of the pressure.
Tokamak has compensate the low pressure by raising the temperature to 100 million degrees.
It's hard.
Also, the rate of heat produced *per volume* in the sun is astoundingly low. The human body makes more heat per volume than the sun core.
The sun compensates this with volume.
Fusion reactors can't do anything useful with such low output rates, they have to be way better than the sun, another factor that forces to use insanely high temperatures.
>>
>>9678508
>brainlet here
>for not looking it up in the real world.
en.wikipedia.org/wiki/
Proton%E2%80%93proton_chain_reaction
>>
>>9679196
anon mentioned per second
>>
>>9684100
Time is in the wrong place.
“Fusion 1 gram of hydrogen in one second results in about 424525 megawatts of energy”
Maybe he meant “Fusing 1 gram of hydrogen results in 424525 megawatt-seconds” That’s 117.9 megawatt-hours (the more usual unit.)
You get the same energy whether the hydrogen is fused in one second or three weeks.

1 gram of matter equals 9e12 joules. Only a fraction of the mass is lost in fusion. 1 gram yields 6.408e10 joules or 64,080 megawatt seconds. Beats me where >>9678573 got his number. He’s too high by a factor of nearly 7.

But even if he was right, his comparison is balderdash!
>https://www.statista.com/statistics/201794/us-electricity-consumption-since-1975/
End users in the United States consumed approximately 3.82 billion kilowatt-hours of electricity in 2017. That’s 10,466 megawatt-hours per day.
So 117.9 megawatt-hours is only a bit over ONE percent of the US’s electricity usage, not 95%. Furthermore, that’s electricity – not energy use. Doesn’t count cars, trucks, planes, and fuel used for cooking and process heat.
>>
>>9680592
>Mass is never "converted into" energy.
>Energy can simply be transformed from one kind into another.

I do not understand the point of that remark. Because it changes nothing of what was asked.

Semantics aside, of trying to discern if the correct word is "convert" or "transform" the question is about effiency of that transformation.

Things that seem fundamental but are actually not fully understood.

>static electricity
>cloud formation
>how can we feel eyes looking at us
>how the placebo effect works
>why is the temperature of the universe so uniform?

Add more of these.
11 replies and 3 images omitted. Click here to view.
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>>9684375
>Im pretty sure your ridiculous claim of being able to feel when someone looks at you

Reading comprehension, do you fucking do it?
>>
>>9684384
What did i not comprehend about your ridiculous claim that someone can sense when someone is looking at you?
come on, im waiting,
>>
Laithewaite refutes the linear coefficient of friction in one of the videos where give an experimental demonstration of real anti-gravity. Supposedly Prince Charles went an had a demo at the university over there because he, correctly, thinks that real anti-gravity is highly novel.
>https://www.youtube.com/watch?v=JRPC7a_AcQo
I'm not sure where he puts the strawberry jam on the angled plane, but he demonstrates an anomalous effect in the friction. I think it is related to the Casimir force pulling random atoms downhill at the wavefront of the sliding spoonful of jam as Laithewaite increases the angle of the plane. So, when the Casimir force sometimes pulls atoms down a little bit, that explains the odd way that the jelly slides, maybe.
>>
>>9683005
>how can we feel eyes looking at us

That is mostly understood. There's tons of reflections around us from everything going on that the brain filters out all the time. Since eyes staring at us would usually mean danger, the brain adapted to detect those reflections that indicate that and that's the "gut feeling" you get from your subconsciousness seeing and interpreting those reflections and other environmental cues.
Doesn't have to be reflections, it's like when you tried to sneak up on someone at school and he knew instantly because people he could see in front of him would look behind him, so his brain knew something is going on.
>>
>>9684266
Thanks for the link!

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>let us assume, just for a moment,
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>>9684338
>>
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>let
>>
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>>>>>>>>>>>>>>>>>>>>assume a """""periodic""""" microstructure
>>
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>>9684224
>Thus it follows
>>
>It's trivial to show that...

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Is a blood test for hep c coming back positive enough reason to postpone a presentation, or am I being unprofessional?
I have to give a presentation in a grad physics class tomorrow, and today I got back test results for hep c that surprise and confuse me. I don't really know what to make of it, I feel like it must be a mistake, but I don't want to work on or give a talk right now. Should I talk to the prof' or tough it out?
3 replies omitted. Click here to view.
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>>9684254
Hep C is curable.
>>
>>9684174
Stop injecting heroin and fucking dudes in the ass.
>>
>>9684250
Is it though? I actually thought I might be being a bit autistic by assuming that I should still do it when I think I am going to be pretty upset about this once I feel that it's real, which might be by tomorrow morning. Maybe I should have mentioned it's not a core coruse; just an out-of-area class that isn't supposed to be that serious. The Prof' seemed fine with it when I talked to him.
Plus, I had to weigh it against how unprofessional it would seem to start crying during a shitty presentation so overall I think I made the right choice.
>>9684254
dang that'll suck
>>9684342
oh cool i hope that happens
>>9684356
>Stop injecting heroin and fucking dudes in the ass.
Well it's a bit late for that *now* isn't it?
But seriously, that's the fucked up thing that has me so confused. I've never used any needle-drug; every single needle I've been stuck with was to draw blood or give a like vaccine or shot or something. The only thing I can think of was that I was sexually assaulted once, but that wasn't even penetrative. I was really going into this with like zero worry it would come back positive it's really fucking confusing.
>>
It’s fine OP. Just say you have a medical issue you need to attend to urgently. If you’ve proven reliable previously, people will understand.
>>
>>9684571
just be open and honest with your people OP. no one is going to be mad that you can't make it if youre litterally ill.

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hey guys- nature question here, was the process called when a biome or environment morph into another? I know desertification is a thing. but can other habitats "invade" like that? like is "swampification" or "junglefication" a thing? what are the most common "invasive biomes"?
>>
Sabino Canyon is near there, I think. Are the Rincons? There's a little road in Sabino Canyon that has seven bridges but wasn't on Google Maps as a road last time a I looked but it is now. However, pic related, even the parking lot where you get the tram up the hidden road is colored darkly. On the canyon tour, the tram driver would say, "See that big red stripe on the cliff wall up there? You might think it's iron in the soil but it's really tannins from the tree roots." I think it's the tannins from the leftovers of the torture. The restaurant on top of the Catalina mountans is called The Iron Door, and on Rawhide Clint Eastwood's character was held in tunnels 90ft underground in AZ while a POW during the civil war.

The outhouses on the Sabino Canyon road are the most disgusting things you ever smelled, and Google satellite shows, or once showed, what look to be signs of fresh digging near each outhouse.

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FOUNDATIONS EDITION

previous thread >>9656582

In this general we will be discussing how we would start to construct an AGI, what the data structure would look like, how it's goals would be defined, and what currently available technologies/methods should be implemented.

And once again:
NO "AI WILL KILL US"-TARDS ALLOWED
289 replies and 20 images omitted. Click here to view.
>>
>>9677805
You are genuinely retarded. Look up turing completeness. The hardware doesn't matter.
>>
Anyone else contributing to the open implementation of AlphaZero for chess?

lczero.org
>>
>>9673823
even better, LeelaChess is holding its own against top-50 players with only 2000 nps! Often beating opponents four magnitudes faster at analyzing.
>>
>>9684339
Its processing sounds really efficient, maybe we've got something here. But it still needed to play 1.6 millions different games, so its learning is yet to improve significantly.
>>
>>9684012
http://isturingtestpassed.github.io

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Post graph
Others try to guess the function

Alternatively just post cool graphs
https://www.desmos.com/calculator
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>>
>>9684234
The Heaviside function translated to the left
>>
>>9684234
f(x)=how fat is your mom(%)?
>>
https://www.desmos.com/calculator/dezqlwsp7v
xD
>>
>>9684234
it's 1 or atleast equal to 1, or maybe 0.9999999999 or 1.00000000000001
>>
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>>9683991

How can a formula, neigh, an entire concept be so beautiful and graceful? Is there a better equation out there? I defy you to name a more elegant piece of math.
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>>9680429
op=faggot
>>
>>9681641
wait what the actual fuck

i have to try this
>>
>>9682441
>>9682848
>>9684239
relax, it spits out all the possible combinations for some nxm grid next to eachother along some axis, so you just need to find the right area to look
still pretty cool
>>
>>9681075
Don't they?
>>
>>9681641
Better yet, Dual of a Hyperset:
B* = { B*, B}

University admission deadline was yesterday.
I only searched Computer Science, Informatics and Electronics studies
how fucked am i? also who with me bois?
1 reply omitted. Click here to view.
>>
>>9684466
What majors are the least miserable?
>>
>>9684476
Probably engineering or something to do with construction, everyone there is a bro

I'm in health sciences myself so it's mostly bitches but other than that I like it
>>
>>9684476
no one wins, the more knowledge you have the more miserable you get
then you learn philosophy which tells you nothing in life matters, and that happiness is something we define for ourselves
if we are blinded by our meaningless goals and never stop to think just for once life will just pass us by
>>
>>9684485
>philosophy

Don't listen to this dumb faggot anon, he fell for the STEM meme
Or he's a sociology/psych major which is equally laughable
>>
>>9684485
>philosophy which tells you nothing in life matters

Yeah if you cherry pick the philosophy that reinforces your depressed, apathetic perspective.

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What is the absolute worst instance of incorrect science you've ever seen in a news story or advertisement?
12 replies and 4 images omitted. Click here to view.
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>>9683090
It was my understanding that Watson and Crick discovered the spiral structure of DNA, not the existence of the chemical itself.
>>
Any of the many times the media reports on the scientific testimony given to Congress by an movie actor. Goes back at least to the testimony of noted scientist Meryl Streep about the pesticide Alar, a subject about which she had strong feelings but did not actually know anything.

Not only does this put crappy science into the public record, and into the crafting of laws, but it also helps teach the public that science is just a matter of opinion, and the celebrities are the ones we should listen to on important matters.
>>
>>9684330
Correct. A serious problem.
>https://nypost.com/2015/02/09/10-anti-vaccine-celebs-that-should-come-with-a-surgeon-generals-warning/
>>
>>9684330
Not just testimony given TO Congress.
Statements BY Congress (and other politicians).

Any pronouncement on a technical matter which begins, "Now, I'm not a scientist, but...."
should end with the "but".
You've admitted your ignorance. Now shut up!!
>>
https://news.nationalgeographic.com/news/2012/07/120709-arsenic-space-nasa-science-felisa-wolfe-simon/

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'internships might be a spook but probably not' edition

ITT: discussion of and questions concerning all forms of engineering.

>student or professional?
>level of education?
>discipline?
>current projects?
>anything else?
190 replies and 16 images omitted. Click here to view.
>>
>>9683643
Mechatronics, literally the bastard child of ME and EE purely and solely focused on everything you need to know to build meme robots.
>>
>>9684103
Some of my friends in EE have studied technical programms and worked for a couple of years because poorfags, but that kind of built them a lot of self discipline and they're basically acing college.
>>
Aerospace vs MechE, which is better?
>>
>>9684190
Neat, thanks. What schools have this? I'm looking right now. Also, what are some books to help me comprehend physics and shit.
>>
>>9672513
>be me, junior ee, never had internship or barely a real job
>get offered internship with 12 dollars an hour
>accept
did I fuck up? i'm really just lucky I got a job at all with a 2.8 desu

What is the biggest fraud in science? I have to go with gravitational waves

If gravitational waves traveled in a spiral like pic related, it would take gravity forever to propagate. We know that gravity is a quick acting force.
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>>9684372
>Inertia and motion do not trade.
No, they are properties that every mass has. It's the quality of inertia (since inertia has no quantity) that defines the coherency of motion and it is motion that keeps inertia from being "just inert" forever. Motion does not occur without the ability to change, motion cannot change its own qualities with no direction. This is why inertia "absorbs" motion, but really it's just accelerating it forever towards an "inert center point"(there is none).
"Loss of inertia"- it is in the process of losing the acceleration towards an "inert center" that is never really obtained to begin with. If an object is no longer accelerating, or overcoming that inert point it is "motion", BUT ONLY TO THAT "SOURCE" of inertia. It is now going to be subjected to the nearest "inertia source". It is "motion" to the original inert point because it has lost its inertia. "gain of motion" is simply another acceleration towards another inert point. You have changed the inertia, you gain or lose inertia. It's a never ending cycle and the only way that such a sheer amount of "difference" in phenomena can even occur.
"How do you lose a quality?"
By making it incoherent to what it originally was.

Also, two objects accelerate towards each other with the inert center in between both objects( in space). Each singular objects' rotational inertia has had a '"loss" due to each others distortions, feeding the newly expressed inert center that each object forms in between each other. They both conglomerate into a single rotational inertia greater than both of theirs separate.

>A spinning gyroscope has slightly more inertia than a stationary one.

Really? So they use stationary gyros in vehicles and satellites because it's the same as a spinning one? Are you retarded? Have you ever used a gyroscope? Have you ever tried to topple a gyroscope?
>Slightly more inertia than a stationary one.
so are you agreeing with me or not?
>>
>>9683461

>"Creating inertia with coherent motion"
>coherent motion=/=opposing motion.
What is coherent motion? Don't make up words and expect me to parse your gibberish.

>In order to LOSE inertia, one must have it to begin with.
All mass has inertia.

>With the quality of motion, you most certainly can gain inertia just as you can lose it.
At relativistic speeds, you gain inertia with motion, you don't losr it.

>You are storing motion with the gain of inertia, not gaining motion with the gain of inertia. Just because the motion gets "faster" as accelerates towards the center doesn't mean it's "gaining" anything. It is losing torque and space to express motion, you are losing motion.
Gibberish.

>>9683490
>And what is the string attached to? The spinning arm of the archer. Is the archer "moving"?
Yes, you just said his arm is spinning.

>No he is standing still and releasing his STORED POTENTIAL ENERGY in the form of centrifugal "force". Where does the "centrifugal force" arise from? Oh right, his bodies INERTIA.

Comment too long. Click here to view the full text.
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>>9684467
>so are you agreeing with me or not?
Clearly I am not agreeing with you because you say a spinning gyroscope gains inertia as it slows down, but in reality is loses inertia because energy is effectively mass and when you spin a gyroscope you put energy into it, it bleeds that energy out into things like heat so it loses the energy (mass) you have put into it and thus loses inertia.

I honestly can't help but wonder how much time you have spent trying to redefine motion and inertia or whether you are just copy pasting stuff from somewhere.
>>
>>9683490
>A pressure difference is created which is why my ear works on responding to pressure differences, not "motion"
Again, how is a pressure difference created in your ear if it doesn't travel? It doesn't magically appear out of nowhere, it has to travel from the source to your ear. You lose, admit it.

>Lets measure "time"
>with time
>and say it exists because we measure it with "time"
Wrong yet again. Time is measured by the number of actions of a clock, not time. You are confusing units of measurement with what is being measured.

>It is a measurement. Is there a point you have here?
Are you incapable of reading?

>Motion is a measurement, doesn't exist.
>Inertia is a measurement, doesn't exist.
>Whatever you say exists is a measurement, doesn't exist.

>If inertia is not a force what is being measured?
Inertia is measured by measuring the effect of a force of known magnitude on an objects' motion. A more massive object will not accelerate as much from the same force applied to it. F = ma.

>How do you measure the tendency to do "nothing"?

Comment too long. Click here to view the full text.
>>
>>9684474
>What is coherent motion?
What is the difference between

>ceramic and iron, boron, nickle
>a magnet

Google it

>All mass has inertia.
I just said that

>At relativistic speeds

>Gibberish.
So the sun, which is has a shit load of motion, does not accelerate us toward it 24/7? What is it pulling us towards you dunderhead? "the sun". And what makes a fucking sun? "Oh uh hydrogen moving really fast". Yeah and what keeps the sun intact? "Gravity". Well what the fuck is gravity other than an acceleration towards an INERT CENTER. ACCELERATION TOWARDS=NOT COMPLETE.

>Yes, you just said his arm is spinning.
Where do you go in a full circle?


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

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>mfw calc3
what in the fuck am I doing
why are functions suddenly vectors now
>>
>>9683174
calc 3 was way easier than calc 2
>>
>>9683174
the function produces the vector
the function produces the vector

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I have a question for the science people here on this board, I know it's pretty general but, do you think the future looks bright or bleak?
>>
>>9684378
if you're ray kurzweil pretty bleak
>>
>>9684378
Depends on how far into the future you mean. The ultimate future of our species is definite destruction because the sun will explode or go out.
>>
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>>9684378

>If aliens exist (extremely likely) they will be cunts and kill us.
>If AI gets too intelligent it will turn into a cunt and kill us.
>Global warming, sorry, "climate change" will kill us unless we give loads of money to renewable energy companies.
>Humans are cunts destined to destroy the world with nukes (which are real), which is why we need to focus on getting to Mars (which is a real, physical planet as NASA have proven without question).
>If we don't destroy ourselves, then a meteor, volcano, black hole, or the inevitable heat death of the universe will happily oblige.
>We're evolved slime with no free will. 100% star dust and proud.

Despite these scientific facts, I remain cool and logical. My intelligence doth not succumb to primitive emotions or faith based beliefs.

This ain't a game for the weak, kid, stay out if you ain't got the guts and admire those that do.

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Why are people in this board so obsessed with this?
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>>9679036
I personally don't care about my IQ. I'm confident in myself enough to not be paranoid over some number. Intelligence is only really a means, not an end (for me, at least). I use it as an excuse to discriminate against niggers though, like >>9683660 said
>>
>>9679036
BEACAUSE PEOPLE DONT KNOW HOW TO SAGE IQ THREADS SO INTELLIGENT DISCUSSION CAN REACH THE FRONT BOARD (pronounced, this time, like the herb)
>>
>>9679036
>Asks why people obsess over IQ.
>Never took a MENSA IQ test.

What's your IQ?
>>
>>9683566
The average is decreasing.
>>
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because /sci/entists don't get any (You)s on their papers, so they brag about IQ instead

feels bad t b h



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