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File: s7viggq7cutc.jpg (25.75 KB, 987x783, broken straw.jpg)

 No.393814[View All]

you should be able to solve this
24 posts and 16 image replies omitted. Click View to see all.


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Don't ask stupid questions




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God Awdrii don't you know anything. You can only wear a tie if your entire outfit is made out of ties.


is yours not?


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Of course it is


hair ties??


>Looking straight down on it from the side



It's badly worded but they mean view point is as pictured from side of glass. Maybe it would be good to reword it for the meme? Idk what the best wording would be tho.


i wasnt sure what the funniest balance was of actually making sense lol

probably replace "down on" with "at"


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File: psv374t6jchs.jpg (96.83 KB, 960x567, 1444157529100.jpg)

Should be able to solve this. It's just elementary geometry.


Is this the one that falls into place once you notice it's an isoscoles triangle and they drew it troll scale? I don't have any paper where I am currently


rad is literally unable to resist doing any math problem she sees :3


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How did it get stuck in water?


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Some people value their intellect highly. Math is considered to be a smartypants thing to do and hey, it's not a complete lie. It's pretty smart to make problems smaller until you can solve them.


File: bzim0qj10zr4.png (19.53 KB, 256x515, diagram-to-scale.png)

Right, they didn't draw it to scale. But even after seeing it drawn to scale (attached), it's still not easy.


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Fuck you, I solved this shit last time


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E-Man are there any spiderman stories you recommend? Peters always funny in the little snippets I find.


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You're all a bunch of nerds.
especially mike


I wish I could understand the question so I could answer it

If you submerged it at 36º, the the submerged part is still going to be at 36º.


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Alright, so assuming that no reflection occurs and that the glass won't affect the image that we see, we could in theory calculate what we see, by using Laws of Refraction.

Grey is the straw, blue is the water level, and red is the vertical we're measuring from. Yellow is a ray of light that is entering the water at the same angle as the straw, so we can see how vision of the object distorts when entering a slower medium. Using Snell's Law, and the Refractive Indices of air (1.0002) and water (1.3333…) we can calculate that this specific beam of light will be only 26º from our vertical when it travels in the water.

Now look at δ, the point where the light hits the bottom of the glass. When observed from outside the water, our eyes see it as if the beam continues through the water at the same angle as it was in air, to τ instead (marked by the orange line). That is why we get a distorted picture in the first place. Where the straw physically is, we see the empty space just below it.

Therefore what we see vs. what is physically there is offset by around 10º, and with that, find out that the straw appears to be roughly 46º from the vertical when submerged.


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I just realized that we only have Avenging and Amazing on that list.
ALright, hoooollldd on.


File: gep0evz8jzsw.jpg (86.1 KB, 500x450, 1346551740253.jpg)

>The complete Ultimate Spider-Man
Back when Mahvel launched the Ultimate line, the only comic of theirs that didn't shit the bed in the end was the Spider-Man run. It's pretty fun to read and a younger Peter means you get all that fun juggling high school and super heroism stuff.

>Amazing Spider-Man Pre-One More Day

That includes the original Spider-Man story. All of the iconic Spidey stuff you've ever seen comes from this. Everything from Venom's first appearance to Spider-Man holding up a fucking monorail train is in this.
Basically any Spider-Man page I've ever posted that isn't Ultimate or Avenging is from this.

>Maximum Clonage/ Maximum Carnage.

Now see, hyper autists like Linkara and other comic book "Critics" will tell you that they suck and you shouldn't read them.
But you need to understand that these people are the gayest men/women to ever live. They are fucking Troglodytes who wouldn't know fun if it fucked them to death.
Maximum is the most insane, goofy, and idiotic spider-man shit you will ever fucking read, and it's the best.

>Miles Morales: The Ultimate Spider-Man.

The black Spider-Man. Not the symbiote, as in the black kid. His first three arcs came out before Marvel was completely over run by mouth breathing tumblrites. Instead of shit like social justice, Miles actually has to deal with things like villains that are stronger than him, protecting loved ones, and learning how to deal with the fact that he has Spider-man powers.
Anything after Ultimate that features Miles isn't worth reading, though.

>Kraven's Last Hunt.

I can't explain this one without spoiling the premise. It came out in 1987 and it still holds up to this day.

>Spider-Man: Reign

Peter killed MJ with his radioactive Spider-sperm. Other than that it's sad as fuck.

>Avenging Spider-Man

The first few Arcs are fucking amazing. Basically existed as a big fuck you to the Superior Spider-Man story that was going on around the same time.

>Spider-Man Noir.

I'm putting this here because I have to.

>The Scarlet Spider

It's about Peter's clone brother Kaine after a story where he was resurrected. Scarlet Spider's story takes place in Texas, he's basically an angry, stronger version of Spider-Man who's less agile and doesn't have Spidey senses.

There are more, but I just recommended close to 1000 comics, so you'll be fine.


E man pls share Gwen Poole if you have it.
I saw it on 8ch co and it seems neato.


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>Gwen Poole.


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y is it bad?
It's one of the non-shit books Marvel has out right now afaik.

Also, why no Thor God Slayer in your reccs?


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Because it's called God Butcher and it's there.


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Also, you need to specify which PG run you're talking about (i.e. the 2005-2007 one iirc).

P.S. I just saw the God Butcher reck in your 2016 edit. So I rescind that, BUT I will ask that She-Hulk under Byrne be there as a saving throw.

MvC3 basically made it normie knowledge, but She-Hulk was busting the 4th wall prior to Deadpool.


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Thoughts on the Black Panther movie?

Actually, what were your thoughts on the superhero movies that came out this year?


That's fairly numerically close to the answer but I don't think its the right approach to the problem. Under your model the shape of the container is not relevant. Because we are looking at the start straight on at an vector perpendicular to the plane you have drawn if the waters surface was flat and also along that plane there would be no distortion as all rays coming out to us are perpendicular to the plane of the water, assuming infinite viewing distance. The distortion is caused by the cylindrical shape of the water held in a cup. I think lol, I don't have like a fishtank to stick a straw into and see if it bends so maybe I'm wrong


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I was excited for years until it was commandeered by the we wuz crowed.
Considering all the rewrites and rebranding it had, I'm probably not going to watch it.

I watched GOTG2 and thats about it. I don't watch that many movies anymore and I don't really give a shit about "Lets pretend we're Joss Whedon" movie #3102.

Cinema in general is pretty shit these days, I'm fine with just not watching movies.


Superior Spiderman is superior


Confused where you got the 10. Aren't you adding 20?


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t. shit-taste pleb.

Real shame that. Even more so with that The Crew that they were launching and cancelled 2 issues in. You know, the americop robots they had in that story deserved to be in a better story.
Look at their Dr. Doom -esque hems on their shirts and I can't help but think of some Kirby story about America policing the world in the 80's or 70's.
Shame, I just loved the design on those baddies.


What you see compared to what's physically present is offset 10º, which I got from seeing how a beam of light would refract at that same angle. It's like if you picked a spot on a wall to stare at, then looked further down, relative to your eyes that initial spot has moved up. Except in this case, refraction is changing your viewpoint instead.

Though the answer is off by 1º, since I didn't consider the round shape of the glass. My answer without rounding during calculation was 45.8º


So just ballparking an offset based on the picture? How would you model other angles that are less close to the picture shown?
Does the Snell's law calculation factor into your answer?


after talking to a TA im pretty sure the numerical similarity is completely coincidental.

im curious however whether for all angles of straw doing it this way leads to a very close answer or not. though not enough to do the math tbh

the 10 is cause snell's law calculated a beam of light coming in at 36 going out at 26 and so the 10 is the angular offset between them


Shouldn't be a coincidence, I gave your answer another look over. Where you're calculating light from the side I'm doing it from a point parallel to the straw. I was wrong because the question asks for the answer to be looking on the glass from the side, however if this were a case of looking into the water from above, or looking into water without walls or glass around it my answer would be correct.

I just found a video that does a pretty good job at describing it in the way that I was imagining it: https://youtu.be/jxptCXHLxKQ?t=162

>rad assumes I ballpark answers and make assumptions from the diagram
I-I'm not an idiot you know
I may have rambled a bit writing my steps but I calculated everything properly


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The problem is interesting because of the perspective. The way refraction is taught they frequently like to show a glass and straw from the side like this to demonstrate "look refraction!" But then they only walk you through the much easier problem of the viewing angle you used. It's neat to force you to back up and demonstrate you really grasp what's going on with the original typical example.

It might be interesting to solve the problem symbolically for arbitrary angles then take the way you did it, plot them for the full range of possible angles, and see how close fit your way works as an approximation, it's less mathematically intense to do it your way, I wonder if it stays within a few degrees the full range or if it was coincidence?


File: m952h4gpnitc.png (45.6 KB, 1187x654, Screenshot from 2017-07-31….png)

So it looks like as long as your angle from the vertical is less than 45 this approximation pretty much holds true.

If you have an angle greater than 45 your "cup" is wider than it is tall so clearly it is no longer a cup. Therefor this works for all cups.


File: cln4iju3smio.png (32.41 KB, 1369x664, Screenshot from 2017-07-31….png)


File: myas0wpb943k.png (27.29 KB, 1366x662, Screenshot from 2017-07-31….png)

log scale


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Lol what a mindfuck would it be if the question asked for 31 degrees. We should change the image macro to ask for 31 before posting this elsewhere on the off chance that someone makes a similar mistake, just to increase confusion.


>If you have an angle greater than 45 your "cup" is wider than it is tall so clearly it is no longer a cup. Therefor this works for all cups.

That's really cool how that worked out, so it wasn't just coincidence. I wonder what 31º means in this situation, since it's the point of intersection for both methods.

Thanks for taking the time to do all th-


File: uaos40n22p6o.jpg (25.62 KB, 987x783, broken straw meme new.jpg)

>how can we make it worse
~rad 2017

i wonder if we can post this on /sci/ or something

i dont think 31 means anything physically its just where the approximation happens to be closest. sort of how the small angle approximation doesnt mean anything mathematically but is fairly accurate and useful. in so far as anything related to math problems about straws in cups can be considered in any way useful… now we just need a similar formula for angles above 45 so we can solve for bowls too

arent you glad that the homo increases more than the hetero :o


Lol 31 how much would you have been doubting life if Delta's answer was like dead on numerically correct. Now people who do it right will worry they over complicated things.


File: 1fe8z3kvt6y0.png (1.93 KB, 187x17, Screenshot from 2017-08-01….png)

its literally the same answer????

>when you spend hours drawing triangles for no reason

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