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https://sites.google.com/site/scienceandmathguide/
>>
Reminder: /sci/ is for discussing topics pertaining to science and mathematics, not for helping you with your homework or helping you figure out your career path.

If you want advice regarding college/university or your career path, go to /adv/ - Advice.

If you want help with your homework, go to /wsr/ - Worksafe Requests.

Post unis, discuss your major etc
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>>8511114
14 days until I find out if I'm accepted here, electrical engineering. I really like physics though and it was difficult to make the choice but I figured there's probably a significant overlap.
If you dont mind, I have questions:

How do you like it?
What year are you?
Do you know any electrical engineering majors?
Do you know how large the overlap (if any) is between Physics and Engineering?

Thanks
>>
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>>8511174
>Wageningen
hehe farmer boy
>>
>>8511317
Where are ya from?
>>
Harvard

Triple Major in Electrical Engineering, Computer Science, Economics

5th semester
>>
University of Melbourne, Economics and Finance

Didn't see one in the catalog.

Diffeq problem here:

How do you know to place these Rs into this problem? Above the black line is the first example problem I did, so I just figured "oh, U must just be the product of X(x) and T(t)," so I tried doing the second problem like that only to see that they took a completely different route. How do I know to do that? I feel like I don't get what U is on a conceptual level.
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>>
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>>8511455
They both have a density of zero because they both have a weight of 0.
>>
sqrt(11-4*sqrt(7)) = sqrt(n)-m
square both sides...
11-4*sqrt(7) = n-2*m*sqrt(n)+m^2
n+m^2=11
2*m*sqrt(n)=4*sqrt(7)
n=7
m=2
>>
>>8511455
Density is mass over volume, not weight
>>
>>8511506
Meant for>>8511474
>>
If you want to prove that the series of general term Un converges, can you prove it by saying that something superior as -1*Un converges too ?
(Un > 0 for all n.)
Doesn't look right to me.

>>8511266
Have you tried Mr. Euler and/or changing variables ?

F
>https://www.nasaspaceflight.com/2016/12/roscosmos-progress-ms-0465p-to-station/
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>>
>>8510434
It's a meme from a COD game
>>
>>8510489
Is this a flow-chart of the Soviet part of the space-race?
>>
>>8510532
>first launch vehicle with two failures to ISS
It's also had more successes to the ISS than every other cargo vehicle combined.
>>
>>8509701
F
>>
>>8510766
And just as many failures

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Is math a science?
>>
>>8511478
A formal science, yes

And it can be applied to the physical science as well but it's not part of physical sciences
>>
>>8511478

It's just a language, like piglatin.
>>
>>8511478
No.
>>
>>8511478
How do you define science?
>>
>>8511478
Yes,

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Hi, level 7 atheist skeptic here, I'm curious to know the best books on the nature of consciousness and neuroscience, from things like how the brain processes information, how consciousness arises, and why human beings think and act the way they do according to the physical makeup of our brains, or whatever other subjects about the brain you personally find interesting enough to read a book about with the brain!

I find it especially interesting the studies I have been reading about why some people are conservative vs liberal, and it has a lot to do with your amygdala, people who are more conservative have a higher fear and disgust response. That has changed my perspective on politics a lot, because I stop looking at it as solely a matter of your choices you make, and factor in more how a person's human nature comes into play. That's something that really interests me.
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>>8510854
Being an atheist has to do with the OP because a lot of times people equate consciousness and the mind to spiritual and metaphysical ideas, which I find retarded and don't have anything to do with what I am looking for. So, it's like that, but I know that immediately something that's implied isn't automatically picked up, because fuckers like you probably still don't understand the point of why I would say that, and keep misunderstanding the world with your idiotic spiritual beliefs and misunderstanding of rational thinking, you retarded fuck.
>>
>>8511162
thoughts are metaphysical by nature so gg youll never get any scientific answers
>>
>>8511326

i contest this.
>>
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>>8510651
>>8510577
I got a book for yahs
It's the first anthology of biosemiotics, a fast growing prospective science that studies the biological processes of meaning making.
https://web.natur.cuni.cz/filosof/markos/Publikace/FAVAREAU%20Essential%20Readings%20in%20Biosemiotics.pdf
Shhh
If springer asks you paid $300.
>>
>>8511496
>if it worked

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Thread for batshit insane but theoretically workable ideas for solutions to global warming

My own:
>Invent a solar powered light panel: solar panel on one side, room light on the other, programmable maximum brightness
>Calculate the greatest area of these panels we can build with all the nonvital resources on earth
>Build that many
>Connect them in a spherical network covering the entire planet at the altitude where the ozone used to be
>Program them to filter out as much of the energy they absorb as the ozone would if it were still intact
>Energy filtered out drifts back into space as light and/or heat
19 replies and 4 images omitted. Click here to view.
>>
>>8511233
>Space moths
If we can get cloth into space surely we can make space mothballs.
>>
Had a notation of airborne bacteria that consumed C02 and fell to earth before multiplying and becoming airborne again, then realized it'd probably result it a runaway global cooling and eventual permanent ice age. Still sounds fun though.
>>
>>8511209
China isn't the problem. It's that fossil fuels are cheap to extract and burn. If China doesn't burn the coal and oil someone else will.
>>
>>8510265

Your retardation inspires me.
>>
>>8510286
Probably the only viable option considering where we're at.

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I don't know if this is the right board, but I'm trying to get good at chess. Does anyone know any tips and tricks to help me improve? Or good chess books / tutorials?
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>>8510843
>>8510848
>>8510878
>>8510973
>>8511094
>>8511098
>>8511272
>>8511394
>>8511399
>>8511407
>>8511419
>>8511440
>>8511447

>(((((((((((((((((((((((((Chess Master))))))))))))))))))))

Chess is a waste of time. If you were truly as smart as you think you are, then you would realize this. The only pursuit worth the time of a highly intelligent man is the study of and contribution to Pure Mathematics. (If you're not smart enough for Pure Mathematics, then physics is close enough.) If these "Chess Masters" were anything more than intellectual midgets, I would be in despair, for we have lost some of the minds we need to bring humanity as a whole toward True Enlightenment. But I'm afraid that anyone who has decided to dedicate their lives to Chess would have never been able to pursue anything else, let alone Pure Mathematics, because they have the mental aptitude of an ape. These "Chess Masters" are mere memorizers. They do not understand. They regurgitate. Therefore, nobody who chooses to play a petty game instead of contribute to the knowledge base of humanity would ever be able make any contribution to Pure Mathematics, and thus there is no loss.
>>
>>8511468
>These "Chess Masters" are mere memorizers
this
Its all about who memorized more combinations. Thats why computer beat man in this game and thats that forever. Football is more challenging for processor than fucking chess. overrated bullshit
>>
>>8511468
Do you realize that chess is an open problem in mathematics? You're right about chess masters being memorizers (some may have even memorized so much it becomes subconscious intuition) but "Chess is a waste of time" goes completely against what you're arguing. Maybe you meant "Playing chess is a waste of time", but really when you think about it playing any type of game is a waste of time, that's the point.
>>
>>8510843
Start with the greeks
>>
Just playing a lot of games is not Good advice. You'll probably make the same mistakes and get disencouraged. Read The Winning Chess series by Yasser Seirawan. Do the puzzles. It will help you a lot.

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Hey guys whats up, I'm a cancer researcher.
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>>
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Greetings everyone, I am Engineer
>>
>>8510955
>>8510959
>>8510964
Post the one where the girl has her hand on the heating element of the sodder tool
>>
>he uses bench paper
baby
>>
>>8510964
>engineer
>pic isn't dude getting butt fucked.
You got it wrong m8.
>>
>>8510955
you're not a cancer researcher, you're a "cancer" researcher pajeet

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https://youtu.be/C9SiRNibD14
"Western knowledge is very pathetic to say the least and must be decolonized."

Do you agree with her?
>>
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>>8511482
>being this slow
>>
>>8511482
Yes, we need a society based on decolonized nigger knowledge.
>>
>>8511482
Yes.

>whites study science
>use it to build factories that mass produce xxl buttplugs and research anti hiv medication

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>the universe was created 13.8 billion years ago

What was around 13.81 billion years ago /sci/?
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>>
Any theories with an ever expanding cyclic universe? Each long heat dead universe suddenly exploding into energy?
>>
>>8511354
There are many people who hypothesize such things, but it's all purely speculative as far as I'm aware.
>>
>>8511353
means you can prefer jump blues and rock n roll instead.
>>
>>8510743
>anything being before the existance of matter, time, and energy
>>
>>8511487

what are you saying? people don't seem to get that im saying that maybe the big bang isn't the beginning.

>inb4 MRI scans reading brain activity

No. I meant actually reading your minds, your inner voice, your deepest, darkest secrets, the secrets that even your mum doesn't know about, the secrets that you yourself don't know about because its hidden so deep inside your subconscious
>>
>>8511428
Yes and more.
There, your question has been answered. Close thread.
>>
>>8511432
>Yes and more.

Hold up buddy. How?
>>
>>8511435
If I knew how then that would mean that I discovered it.
>>
>>8511435
no, not without being extremely invasive.
>>
>>8511428
"...troll..." "...troll them... just for today..."

I have already read yours OP.

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Why would one drug work when another very closely related drug had no effect? For example, why would nortriptyline be effective in treating one of its indications when amitriptyline wasn't? The only difference between the two is a missing carbon at the end of the nitrogen.

It's not like enantiomers where one might be more active because of its completely reversed structure.
6 replies omitted. Click here to view.
>>
>>8510536
>specific receptor doesn't bind to everything equally
Gee I wonder why it doesn't make sense
>>
>>8510536
Because nortryptyline is a metabolite of amitriptyline, you first have amitriptyline acting on the brain, then as its metabolized you have nortryptyline created, so now you have decreasing levels of amitriptyline and increasing nortryptaline, but you have both because metabolism isnt instant.

When you only take nortryptyline you dont get the effects of amitriptyline.

Wikipedia states this AND has the binding affinities/action on transporters of both drugs, compared
>>
>>8510786
That doesn't answer my question on why the metabolite would be effective when the prodrug that metabolizes into the metabolite doesn't work.

I understand that they bind differently, but unless amitriptylene interferes deconstructively with nortriptylene then I don't understand why nortriptylene on it's own would work when amitriptylene doesn't.
>>
>>8511486

Someone already explained this in the thread, different steric interactions with the receptor protein = different magnitude of effects, and sometimes even different effects altogether like in the case of functional selectivity.
>>
>>8511501
still doesn't make any sense. at some point all of drug 1 will be metabolized into drug 2. drug 1 was not effective at any point, so pure drug 2 shouldn't be either.

Why do biologists care about preserving species diversity, but not human diversity?
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>>8511153
Pro tip, actually study biology and you'll figure it out for yourself.
>>
>>8511160
Post 2 nails it, yet everyone just keeps posting. Quieten down, now.
>>
>>8511153
>/pol/ will never leave
feels bad, man
>>
>>8511371
>implying /pol/ isn't right sometimes.
>>
>>8511323
>>8511371
or you could just explain it to an ignorant faggot like me

A steel projectile of 4 grams traveling at 6000 feet per second has 6.6890e+3 joules (4.9336e+3 foot pounds) when it encounters an Eddy Current Brake.
How many watts are needed to power the brake in order to slow the projectile 50 feet per second in o inches,in 12 inches, and in 24 inches?
How hot would the steel become?
If you can't solve this problem please point me towards the equations I'd need to solve or what steps i'd need to take to solve.
2 replies omitted. Click here to view.
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>>8511214
at 100% efficiency wouldn't input power into the machine only need to = 6.6890e+3 joules per second to stop the bullet in 1 second?
>>
>>8511146
>Imperial
>>
12 inches, 6000*6689 watts
24 inches, 3000*6689 watts
0 inches, impossible.

Power = F*v = change in Joules/s

Read a book, nigger.
>>
50 feet per second in 0, 12, or 24 inches doesn't make sense anyways.
>>
>>8511456
After traveling x inches the velocity of the projectile is now 50 fps



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