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Physics. Forces. Springs. by Cyril Nucklepodging - Sun, 16 Jul 2017 10:24:40 EST ID:tgwdoW8d No.15535 Ignore Report Reply Quick Reply
File: 1500215080231.png -(16883B / 16.49KB, 973x331) Thumbnail displayed, click image for full size. 16883
Does it matter what ordeer 2 springs are in, if youre stacking them and measuring the total force?
>>
Esther Dartfield - Thu, 20 Jul 2017 19:06:29 EST ID:A2j/BW/W No.15541 Ignore Report Quick Reply
no


Calc by Fry & Leela - Sun, 16 Jul 2017 12:43:38 EST ID:Rhgh4/nK No.15536 Ignore Report Reply Quick Reply
File: 1500223418101.jpg -(12838B / 12.54KB, 398x66) Thumbnail displayed, click image for full size. 12838
Can anyone tell me where to begin with this problem? I'm clueless. Our professor didn't cover it. I imagine start by taking d/dx and plugging the values in at some point?
Thanks
>>
Cyril Clugglefoot - Mon, 17 Jul 2017 18:43:04 EST ID:tgwdoW8d No.15537 Ignore Report Quick Reply
So... when the derivative crosses the y-axis, that means that your function, x2x-ex, there has changed directions. So that means that ANY time your d/dx crosses the y-axis, it creates a "local" maximum value, which may not be the overall actual max peak.

I believe you:
  • find the derivative
  • find the zeros (what's that process called again?), i.e. solve for zero
  • plug in each x value you found into the original function, x2e-x -> compare all y values to find the greatest


Correct me if I'm wrong, it's been 3 years.
>>
Fuck Murdridge - Tue, 18 Jul 2017 16:12:50 EST ID:XBxBdy5C No.15538 Ignore Report Quick Reply
>>15537

Pretty much this, but check the values at the endpoints of the interval too not just at local Mac/mins.
>>
Martha Hellyford - Wed, 19 Jul 2017 00:10:34 EST ID:cezjQDuj No.15540 Ignore Report Quick Reply
>>15537
>So that means that ANY time your d/dx crosses the y-axis, it creates a "local" maximum value
Oops, I meant
>creates a "local" max OR min value, i.e. just a peak/trough somewhere
It's only a max if the derivative's slope is negative around that zero


Pleb Contemplates Curvature by Pleb - Mon, 23 May 2016 14:22:48 EST ID:BB0KLoxX No.15128 Ignore Report Reply Quick Reply
File: 1464027768468.png -(150891B / 147.35KB, 769x595) Thumbnail displayed, click image for full size. 150891
I am certain i am missing information so i appeal to you brainy smarties to educate me However this also may be a physics questions. I dunno.

Do curves actually exist? Meaning at the smallest point possible (I would assume planck length) would it not be a straight line from point A to point B then a second straight line from point B to point C etc etc? Only upon pulling back far enough to no longer see the individual points does the curve appear?
30 posts and 4 images omitted. Click Reply to view.
>>
Matilda Suvingtene - Thu, 18 May 2017 03:23:17 EST ID:YEemZCud No.15503 Ignore Report Quick Reply
>>15474

nigga have you even taken psychedelics? are you unaware we exist within a holographic cosmic fractal?
>>
Eliza Grimstone - Fri, 19 May 2017 15:33:10 EST ID:lub1zF0h No.15504 Ignore Report Quick Reply
>>15474

>hurr I can't measure it therefore it's not real

Nope, that's not how things work.
>>
Beatrice Sapperperk - Sat, 20 May 2017 01:59:48 EST ID:VoDJt227 No.15505 Ignore Report Quick Reply
>>15475
>You can't know that you're on a screen made of discrete pixels.

Do you not know that you're made of discrete particles?

>What if you "really are" in such a space but the laws of physics in your world make models which take space to be continuous much more accurate than any dicrete models you can produce?

That's not how it works. We make models to help us understand nature. If a model is successful at explaining things, we attribute to it the quality of reality. This is called model-dependent realism.

>You can't know that way down there is some discrete object which makes everything up

Again, you provide no reason why it's impossible to know this. In the case of the pixel-screen universe, the surface of an object would change depending on how the object was oriented. This would measurably affect the friction experienced between objects.

>Occam's razor says that you should behave as though space is continuous.
Comment too long. Click here to view the full text.
>>
Martha Surringstidging - Sat, 15 Jul 2017 23:59:35 EST ID:cJu72Hgm No.15534 Ignore Report Quick Reply
>>15128
curves exist about a point, not at the point itself
8)
>>
Charles Fillylitch - Tue, 18 Jul 2017 18:12:59 EST ID:lub1zF0h No.15539 Ignore Report Quick Reply
>>15534

From your reductionistic point of view, how can any physical or mathematical model bear any relevance to reality outside of approximation? What is the point of doing mathematics or theoretical physics outside of productive application if ultimately they do not reflect reality? I think from your point of view the best results in these fields are mere coincidences and logical trinkets that have the same value of clever wordplay in a joke.

I think if you continue down that avenue, mathematics is just the domain of specious logical combinations deduced from baseless intuitions that are ultimately of no relevance to "out there".

It is the physical version of the philosophical point of view that all experience is sensory illusion, that humans are ultimately barred from experiencing truth or reality, the modern interpretation of religious wretchedness, and the negation of the humanist conception of what people are capable of doing through the right and rigorous exercise of reason.


What's the biggest number? by Nathaniel Sacklespear - Fri, 23 Sep 2016 09:54:08 EST ID:XssdERJk No.15209 Ignore Report Reply Quick Reply
File: 1474638848911.jpg -(72632B / 70.93KB, 720x960) Thumbnail displayed, click image for full size. 72632
Assume we had all the possible methods of information storage in the universe and all the resources of the universe at our whimsical disposal.

What's the largest number we could put down in some kind of recording before we ran out of universe?

So I guess the core question I'm asking is what's the most compact way to write large numbers? Is there anything that beats out scientific notation? And what's the greatest extreme to which we could conceivably take this?
23 posts and 3 images omitted. Click Reply to view.
>>
Angus Grandfoot - Mon, 29 May 2017 04:50:28 EST ID:lub1zF0h No.15515 Ignore Report Quick Reply
>>15514

Regardless of how much information could be stored in the observable universe by a method of your choice, the issue would be energy to store and access the information.

If there is information stored in a way that there is no physical way to access or decode it, is it really information for this purpose?
>>
Nicholas Fonkinfot - Wed, 31 May 2017 17:07:34 EST ID:lYjTKStM No.15516 Ignore Report Quick Reply
>>15515
Actually no. At least in the sense that TT has been posted in /math/

In a mathematical sense we are not interested how much of the universe has to be utilized to run the storage machine and how much is actual storage.
So I just assumed that the number OP is interested in is a theoretical upper bound of such mechanism in the sense that involved all matter/energy and space. Think of a omnipotent entity outside of the universe re-configuring it. Without actually adding or removing anything.

The number I described would be the number of ways such entity could possibly do that, which by the pigeonhole principle must be exactly the information storage capacity of the universe.
>>
Jenny Hinkinridge - Thu, 01 Jun 2017 22:54:27 EST ID:sMHQkkFd No.15518 Ignore Report Quick Reply
>>15516
In a mathematical sense we are not interested in the universe.
>>
Graham Dartspear - Sun, 18 Jun 2017 10:13:26 EST ID:EJeHrwkJ No.15521 Ignore Report Quick Reply
>>15209
4913
>>
Martin Surrywell - Thu, 29 Jun 2017 15:08:20 EST ID:h0vIir1X No.15532 Ignore Report Quick Reply
>>15209
hiffwe


Math Problems you came up with by Charles Fundlepeck - Thu, 22 Jun 2017 16:37:54 EST ID:jadYTFeE No.15524 Ignore Report Reply Quick Reply
File: 1498163874635.gif -(2096042B / 2.00MB, 338x252) Thumbnail displayed, click image for full size. 2096042
A rectangular piece of cardboard has a length that is twice its width. Squares with sides that measure 1/10 of the length of the cardboard are cut from each corner and the resulting flaps of the cardboard are turned up to form an open box. A maximum of 24 cubes that measure 2 inches on the sides can fit perfectly inside the box. What are the dimensions of the box? What were the length and width of the rectangular cardboard before it was cut and made into a box?
2 posts omitted. Click Reply to view.
>>
James Gembleford - Thu, 22 Jun 2017 21:09:11 EST ID:j58znr37 No.15527 Ignore Report Quick Reply
>>15526
The number I gave before is close to 11. I checked and unless this is a rounding issue I'm either right or setting up the problem incorrectly.
>>
Betsy Cenderhall - Thu, 22 Jun 2017 21:12:25 EST ID:jadYTFeE No.15528 Ignore Report Quick Reply
>>15527
I think you're setting the problem incorrectly. Here's a hint: The width consists of just two digits.
>>
James Gembleford - Thu, 22 Jun 2017 23:49:39 EST ID:j58znr37 No.15529 Ignore Report Quick Reply
>>15528
Oh I was doing squares which are 1/10 the width of the cardboard, not the length.
>>
James Gembleford - Fri, 23 Jun 2017 10:43:03 EST ID:j58znr37 No.15530 Ignore Report Quick Reply
So I now realise that my other answer doesn't really make sense because the resulting box would be the right volume to contain the cubes but not the right height. With that in mind, the solution is easy. Let x be the width of the original cardboard. The length is then 2x and the side length of the squares removed is (1/10)2x=(1/5)x. But this number becomes the height of our box, which must be 2in if the cubes are to fit perfectly inside. Solving (1/5)x=2in we find the width can only be 10in and the length 20in.
>>
Betsy Cenderhall - Fri, 23 Jun 2017 10:54:59 EST ID:jadYTFeE No.15531 Ignore Report Quick Reply
>>15530
Congrats, you got it! I hope others here had fun with my little problem.


Snowflake by Fucking Hegglebeck - Tue, 23 May 2017 23:18:48 EST ID:9ZyxHAkA No.15511 Ignore Report Reply Quick Reply
File: 1495595928911.png -(12305B / 12.02KB, 591x612) Thumbnail displayed, click image for full size. 12305
I made you guys a generalized Koch snowflake. I have a tool now that can produce several variations on the basic idea. Cheers.
>>
Matilda Cruggleputch - Sun, 28 May 2017 18:24:48 EST ID:IRzzwuqV No.15513 Ignore Report Quick Reply
tight shit, OP
>>
Graham Danderford - Wed, 21 Jun 2017 23:05:45 EST ID:j58znr37 No.15523 Ignore Report Quick Reply
1498100745650.png -(10771B / 10.52KB, 534x542) Thumbnail displayed, click image for full size.
This is what I had intended to make at first. It has triangles at the first stage, squares at the second, pentagons at the third, and so on.


Getting into Physics ---> Quantum stuff by Beatrice Sepperhall - Thu, 21 Aug 2014 13:14:21 EST ID:t/8wjLF3 No.14296 Ignore Report Reply Quick Reply
File: 1408641261077.jpg -(125896B / 122.95KB, 1200x930) Thumbnail displayed, click image for full size. 125896
Where should I start? Should I learn a bunch of calculus first? I was recommended University Physics With Modern Physics (Young & Freedman) to start with and then to move to Quantum Mechanics (Bransden & Joachain). At least to start off with.

Any other recommendations or whatever? Besides college and stuff, just on maybe the order you began learning it or w/e? thanks.
4 posts omitted. Click Reply to view.
>>
Lillian Barryshaw - Sat, 30 Aug 2014 04:01:17 EST ID:Gw2IN3ba No.14341 Ignore Report Quick Reply
>>14340
So you're really serious about this, huh? Just out of curiosity, are you planning on buying all these books? Anywho, I used the third edition of Linear Algebra and Its Applications by Lay. But MIT uses Introduction to Linear Algebra by Strang, so I'd go with that. After calculus and linear algebra, you'll want to study differential equations. I used Differential Equations: An Introduction to Modern Methods and Applications by Brannan and Boyce, but Ordinary Differential Equations by Tenenbaum and Pollard seems to be a more popular choice for self-study. That's all the mathematics you really need to get started in QM. Of course the more mathematics you know, the better in physics you'll be. So studying things like probability theory (which again you need to understand the bare bones of), PDEs, and even group theory will help you better understand QM.
>>
Hamilton Docklekane - Tue, 02 Sep 2014 22:21:50 EST ID:n1HpAHmU No.14344 Ignore Report Quick Reply
>>14341
I personally think the study of differential equations is more important to have down before the linear algebra when learning the basics of QM, because then you can get a feel for what Shrodinger's equation is saying, but there is much debate on the proper pedagogy for teaching it. Vibrations and Waves by French is my personal choice for learning diff eq.s and linear algebra/ their applications to physics all in one nice bundle. Also Mathematical Methods in the Physical Sciences by Boas has been a life saver for soooo many areas in physics. I still keep my copy of it from sophomore year in college on my bookshelf.
>>
Archie Worthingfield - Sun, 07 Sep 2014 18:26:47 EST ID:xvgqavvT No.14354 Ignore Report Quick Reply
Here ya go, a full list of exactly what you need to be a good theoretical physicist
http://www.staff.science.uu.nl/~Gadda001/goodtheorist/index.html

Many of the links don't work anymore, so substitute with MIT Open Courseware lectures on Math/Physics or whatever modern books you can find. http://ocw.mit.edu/courses/physics/8-05-quantum-physics-ii-fall-2013/video-lectures/
>>
Barnaby Brellyhick - Sat, 20 May 2017 21:48:22 EST ID:EJeHrwkJ No.15507 Ignore Report Quick Reply
>>14296
Write a paper suggesting a link between chemistry and physics
>>
Martin Murdman - Mon, 19 Jun 2017 22:10:21 EST ID:q/daWEW+ No.15522 Ignore Report Quick Reply
>>14296
Learn calculus, differential equations, linear algebra, and abstract algebra/group theory. Read Quantum Mechanics by Shankar. When they start about euler lagrange equations as a way of doing classical mechanics problems check out Give Taylor's Classical Mechanics.

If you want to go deep the Landau Lifshitz books are essential. Griffith has a good E&M book if you are only interested in learning enough E&M to do advanced quantum. Gordon Baymn's lectures on quantum are really dense, but really well summarize the most essential aspects of quantum, and teach you how to solve some really practical problems (spectroscopy/scatter/super conductivity class shit). Messiah's and Sakurai's textbooks are each good in their own ways.

take acid


Star by Black Hole Son - Thu, 01 Jun 2017 18:14:15 EST ID:Mfduv5of No.15517 Ignore Report Reply Quick Reply
File: 1496355255705.jpg -(92361B / 90.20KB, 960x918) Thumbnail displayed, click image for full size. 92361
How do you determine the quantity of a thing mixed up in other things to a point where the sum total gets blurred by the myriad factors of an æquation?
>>
John Cannerway - Fri, 02 Jun 2017 14:34:58 EST ID:BI+jncva No.15520 Ignore Report Quick Reply
Try stating your question more clearly, if possible. It sounds more like you're not able to determine the quality of that thing because your definition of what thing is lacks the enough specificity for you to even know where to start when trying to extract the appropriate information from where and in what ways to manipulate it to give you a quantity for the exact thing it is you are trying to determine the quantity of.


Best language for math by Simon Sattingbury - Wed, 22 Mar 2017 03:37:13 EST ID:lwS34rUW No.15429 Ignore Report Reply Quick Reply
File: 1490168233477.jpg -(75572B / 73.80KB, 620x1014) Thumbnail displayed, click image for full size. 75572
German?
3 posts omitted. Click Reply to view.
>>
Phineas Chacklestetch - Sun, 09 Apr 2017 02:12:13 EST ID:vrOFV9fT No.15460 Ignore Report Quick Reply
>>15429

I want to add that some German words are things that would be lengthy phrases in english. For instance a famous theorem is Hilbert's Nullstellensatz theorem, which roughly and shittily translated in to english means the zeroes places theorem.

German isn't a better language for math, because mathematical objects are independent of language.
>>
James Sinkinbitch - Sun, 09 Apr 2017 17:24:13 EST ID:6m87/9/+ No.15467 Ignore Report Quick Reply
>>15459
I do agree, but I also think that sometimes language gets in the way of learning.

for instance, closed/open/clopen in topology (using words which have binary meaning to talk about objects which arent binary)

or 'imaginary' numbers

Those things arent hurdles for math people, but I do think they are hurdles when someone is trying to learn math
>>
Fucking Crocklemack - Thu, 13 Apr 2017 22:08:40 EST ID:c0vo/Lfo No.15471 Ignore Report Quick Reply
>>15460
It takes roughly as long to say Nullstellensatz as it does to say Zeros Places Theorem. All that German accomplishes is reducing the number of spaces you have to type.
>>
Thomas Pammerdale - Sat, 20 May 2017 21:41:47 EST ID:1puAuUud No.15506 Ignore Report Quick Reply
>>15429
The lost language of babbaganoosh
>>
John Bliffingson - Wed, 24 May 2017 03:05:51 EST ID:lub1zF0h No.15512 Ignore Report Quick Reply
>>15471

Yes, but there are fewer "z" letters in Zero Places Theorem, and the space key is already one of the most used buttons. It is more economic and eco-friendly over the long run to use long and complicated words that have lots of "z" and 15+ characters.


Mandlebrot Set Via WEbcam Iteration Discoved By Me by Eric Alan Frazin - Sun, 14 May 2017 03:01:43 EST ID:Cv411eOF No.15498 Ignore Report Reply Quick Reply
File: 1494745303297.png -(157083B / 153.40KB, 1366x768) Thumbnail displayed, click image for full size. 157083
<center>
<body bgcolor="black" onmousemove="drawe();">
<video id="video" autoplay hidden height="500" width="500"></video>
<canvas id="canvas" width="500" height="500" style="">
<script>
var ii=177;
var video = document.getElementById("video");
var c = document.getElementById("canvas");33
var ctx = c.getContext("2d");
var canvas = document.getElementById('canvas');
var context = canvas.getContext('2d');
var text = "";
var video = document.getElementById('video');
var mediaConfig = { video: true,audio:true};
function drawe(){
Comment too long. Click here to view the full text.
>>
Eric Alan Frazin - Sun, 14 May 2017 03:05:21 EST ID:Cv411eOF No.15499 Ignore Report Quick Reply
I know double posted in prog but this is a break through in physics, math and comp sci.
>>
Eric Alan Frazin - Sun, 14 May 2017 03:12:08 EST ID:Cv411eOF No.15500 Ignore Report Quick Reply
<style>

canvas{
filter:contrast(4038%);



}
</style>
<center>
<canvas id="canvas" width='1500' height='1500'></canvas>

<body bgcolor="black" onmousemove="drawe" onmousedown="drawe" onchange="drawe" ondoubleclick="drawe;">
<video id="video" autoplay hidden>
</video>
Comment too long. Click here to view the full text.
>>
Phoebe Tillingstone - Mon, 15 May 2017 00:40:31 EST ID:AQ7xCSUt No.15501 Ignore Report Quick Reply
it's a neat little app. can you explain the principals behind it?
>>
Archie Blimmerfuck - Thu, 18 May 2017 01:12:57 EST ID:j58znr37 No.15502 Ignore Report Quick Reply
>>15501
It's autism combined with a severe lack of moderation on the academic boards.


Hyperoperations by Hamilton Nudgebanks - Wed, 29 Mar 2017 16:37:10 EST ID:uqJv93qR No.15439 Ignore Report Reply Quick Reply
File: 1490819830015.png -(109711B / 107.14KB, 790x726) Thumbnail displayed, click image for full size. 109711
Does anyone have any ideas about pic related?
26 posts and 6 images omitted. Click Reply to view.
>>
David Blythestock - Sun, 23 Apr 2017 19:46:31 EST ID:KPDi1EOJ No.15488 Ignore Report Quick Reply
>>15487
Why so secretive? I'll draw you a picture of each of the ways I tried some time later this week. Can't be assed to describe it in words right now, and in any case I wasn't able to finish the double-counting either way I did it.
>>
Charlotte Sengernark - Fri, 05 May 2017 15:59:04 EST ID:thFY31Zj No.15494 Ignore Report Quick Reply
1494014344836.png -(310596B / 303.32KB, 1128x541) Thumbnail displayed, click image for full size.
Here are the two Burton-like configurations I tried.
>>
Charlotte Sengernark - Fri, 05 May 2017 16:14:29 EST ID:thFY31Zj No.15495 Ignore Report Quick Reply
>>15494
Just realized I fucked up the 3^3 on the left picture. You get the idea, I hope.
>>
Walter Surryhig - Sat, 06 May 2017 23:44:26 EST ID:982EzYoa No.15496 Ignore Report Quick Reply
brings back memories of Proofs class. terrible memories...

Can someone remind me what
f: N^3 -> N

means, again?
>>
George Crenningwell - Sun, 07 May 2017 10:56:40 EST ID:thFY31Zj No.15497 Ignore Report Quick Reply
>>15496
It means f takes three counting numbers as arguments and spits one counting number out. For example, f(2,3,4)=16.


Top 10 favourite Integers by Colonel Badtouch - Fri, 04 Nov 2016 15:38:05 EST ID:9bYxsT36 No.15261 Ignore Report Reply Quick Reply
File: 1478288285194.jpg -(104652B / 102.20KB, 640x427) Thumbnail displayed, click image for full size. 104652
Hey guys what are some of your favourite integers? Here's my top 10:
10. 34,236
9. 8
8. 457,893 ( I bet some of you thought this would be higher!)
7. 43.
6. 6 (Imagine that!)
5. 240
4. 9000
3. 7,777,777
2. 7, 777,771
  1. 108
9 posts and 3 images omitted. Click Reply to view.
>>
Nigel Dartwater - Thu, 09 Feb 2017 18:17:46 EST ID:txB+9pVv No.15332 Ignore Report Quick Reply
1486682266851.jpg -(34208B / 33.41KB, 289x420) Thumbnail displayed, click image for full size.
>>15261
10. 15625
9. 11
8. 222
7. 6
6. 50
5. 7
4. 800
3. 22222222222
2. 2919
  1. -7776
>>
Esther Gacklefudge - Fri, 28 Apr 2017 07:13:40 EST ID:ke/fVhEa No.15490 Ignore Report Quick Reply
>>15261

pi.
>>
Priscilla Goodworth - Sun, 30 Apr 2017 21:07:25 EST ID:lub1zF0h No.15491 Ignore Report Quick Reply
1493600845593.gif -(938524B / 916.53KB, 500x281) Thumbnail displayed, click image for full size.
>>15490

That ain't no integer son
>>
Nigel Cronningfudge - Mon, 01 May 2017 13:44:06 EST ID:QC/JAkzH No.15492 Ignore Report Quick Reply
I like 1, 3, 7 & 12. And 24. And 144,000
>>
Martha Deddlestat - Wed, 03 May 2017 12:52:44 EST ID:lYjTKStM No.15493 Ignore Report Quick Reply
The Fermat Primes https://oeis.org/A019434
3, 5, 17, 257, 65537

the form of 2^(2^m)+1 makes them just one too large to use 8 bit or 16 bit binary calculations (which might be alleviated and as such is part of the interest)
And they represent the number of sides of construable regular polygons which are as perfect as you can approximate a circle in their own right, in terms of relative the quality of approximation vs number of digits needed to do the calculation.


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