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What do you think? Give us your opinion. Anonymous comments allowed.
#4596 - lulzforalpsplane (06/02/2015) [-]
If:
-lines make up the 2D and planes make up the 3D equivalent of a line
-and 2 non-parallel planes always intersect in the form of line

Does that mean you can apply the same for higher dimensions?

As in the 4D, or 5D will have its equivalent to a line in 2D just like the plane is. And does that mean intersections between these will yield the equivalent of a dimension below them? ie - two 4Ds will intersect to form a plane (infinite POIs in the plane)

Someone get what I'm trying to say?
User avatar #4638 to #4596 - nought ONLINE (06/06/2015) [-]
yes
#4603 to #4596 - bwiedieter (06/03/2015) [-]
You can have 3 spatial dimensions plus 1 time dimension, or 4 spatial dimensions.
You can achieve the latter by making (just as an example) two simple 3D cubes and then joining every point with its respective counterpart in the other cube. Boom, you have a 4D object viewed in 3D space. Higher dimensions mean (in its simplest terms) more cubes that you set into relation to each other.
For 3+1 (3 spatial + 1 time-dimension), you take your original cube, and then just "drag it" by a vector of your choice, so that the former cube fills all the space between your staring points and end points.
User avatar #4602 to #4596 - xsnowshark ONLINE (06/03/2015) [-]
Every line that represents a dimension must be orthogonal to all the other lines (ie. at 90 degrees to all other lines).

You could have a picture where lines make up higher dimensions, but I'm not sure how you would visualize it.
User avatar #4587 - shaunata ONLINE (05/31/2015) [-]
So there is a theory that the atomic bomb testing we did in the 40's was the influence as to why cancer became more common in the 60's and beyond. Any thoughts on this?
User avatar #4648 to #4587 - abbieru (06/09/2015) [-]
No, radiactivity levels are not hazardous enough to have a significant raise in cancer levels, they did the testing under controlled distances and circumstances.

This video goes away from the topic a bit, but it's good to get a hang of it
www.youtube.com/watch?v=TRL7o2kPqw0
User avatar #4639 to #4587 - nought ONLINE (06/06/2015) [-]
well, given there is no evidence of radioactivity for most people with cancer, I don't see any evidence supporting that
User avatar #4590 to #4587 - skoldpaddacommala (06/01/2015) [-]
What kinda of cancers? Like lung/throat cancers? Cause there were quite a few hippies during that time, all smoking away like there was no tomorrow. Could be other factors as well. Production of processed foods takes off and gets more advanced. We become lazier and more gluttonous. Plus, technology to identify and treat cancers are always improving. Especially when we reach the atomic age where we utilize electromagnetism to peer into a human body.

If the atomic bombs had any influence on the statistics of cancer, it would only be because of the people America dropped the bombs on.
User avatar #4594 to #4590 - shaunata ONLINE (06/01/2015) [-]
They say cancers in general. But brain cancer and breast cancer is the most discussed one in regards to nuclear testing.
#4588 to #4587 - raeptiemx (05/31/2015) [-]
Cancer increased due to various reasons with most important being early diagnosis and treatment compared to back in the days when people realized something went wrong when they had seizures and/or kept on bleeding through all of their orifices. Also the boom occurred someone might say due to the increased stressful life that everyone had to put up with in the big cities.
Also let's not forget that we're getting older and thus our chances of getting cancer get higher since the body is filled with DNA errors/short telomeres/mitosis gone wrong/weak immune system prone to cancerous formations.
We realized that smoking is indeed very detrimental to health and we see it from all the people in the hospitals with oropharyngeal/lung cancer.
Let's also not forget that cancer is a group of diseases with different causes (environmental and or genetic)
and thus it feels like the atomic bomb theory is not that solid.
Besides the Manhattan project helped us with radioisotopes in diagnosis of cancer.

User avatar #4589 to #4588 - shaunata ONLINE (05/31/2015) [-]
I can see why all those factors contribute to the cancer statistic we have today, and we do live in a stressful society, this can only weaken the immune system and create more DNA damage, thanks for input.
User avatar #4595 to #4589 - dudeheit (06/01/2015) [-]
And Keep in mind that while growing older your cells doesn't divide as fast as they used to be, meaning: just because someone who has cancer at the age of 90 can die a natural death because he was just simply to old and not because of his spreading cancer - just a side note but raeptiemx did a good summary
#4586 - phanactssonjoe (05/30/2015) [-]
do you think we already met intelligent life but they're not telling? like the rule of not to tell the public because they dont think we can handle it
User avatar #4714 to #4586 - mookiea (06/27/2015) [-]
I'd be pissed to be honest. I would love to meat some other intelligent lifeforms. I would love to explore the universe and witness the beauty of different planets. I'm ready alien peoples. take me.
User avatar #4652 to #4586 - gmarrox (06/10/2015) [-]
The Fermi Paradox is a good explanation as to why that's highly unlikely.
User avatar #4597 to #4586 - nimba (06/02/2015) [-]
no
User avatar #4591 to #4586 - sugoi (06/01/2015) [-]
So basically men in black?
#4593 to #4591 - phanactssonjoe (06/01/2015) [-]
the government cause theyre the ones that would know
#4585 - dvmaster (05/29/2015) [-]
Anybody knows about good books about permutations, combinations, and probabilty?? I have an exam on Wednesday and I'd like to read more about it.
#4604 to #4585 - bwiedieter (06/03/2015) [-]
Books no, but I can heartily recommend the videos from Numberphile (Brady Haran and Prof. James Grime), e.g. the ones on decifering Enigma.
In general, everything from the University of nottingham is 100% worth a watch if you don´t already know them.
#4584 - anon (05/28/2015) [-]
can you help me out with this exercise? " a ball has radius 11 cm and weights 430g, it is filled with air that has overpressure 85kpa to surrounding atmosphere. Atmospheric pressure is 98kpa and the temperature is 295.15 K.

a) if you stab the ball, what volume of air would have flown out of it? at given conditions.( the answer should be 4835ml)

b)what is total weigh of air inside the ball, if his molar weight is approx: 29? (the answer should be 12.06g)

c) how heavy weight you would have to add to the ball, so it would be capable to sink underwater assuming that the weight will be made of metal. (again the answer should be 5133g)



so my question is, how to solve this?
#4592 to #4584 - anon (06/01/2015) [-]
i came back to this exercise and managed to solve part b)
if anyone is interested it is just simple PV=RnT, in which the V is volume of the ball itself

so to elaborate (if it is the cirrect word): pressure is 183*10^3 Pa, volume is 5.57245*10^-3 m^3, R is gas constant 8.314 J*kg^-1*K^-1, n is m/M g in which M is 29 g*mol^-1 and T is 295.15 K. you put all this shit together and come up with this equation m = (PVM)/(RT) [g]
#4605 to #4592 - bwiedieter (06/03/2015) [-]
I don´t know why, but I hate problems like this one. With a passion.
#4608 to #4605 - anon (06/03/2015) [-]
Do not be afraid, for i bring result for problem a),

i was calculating and shit all the time always just one foking step from right answer, only simple subtraction ( if it is the right term) away.

first, again, using PV=RnT yo get volume of gas at temperature 295.15K and pressure 98KPa which should be around 10litres, and then you substract (?) the volume of ball which is around 5 litres and in the end you get that 4835ml answer. ( or you can use adiabatic expansion equation: P1V1^y=P2V2^y to get V2 and then the same substraction. by y i mean gamma (sorry) if you want to know what that mens just ask, forr air y= 5/3)

and c) is just Fg=Fhyd gravitation force = hydrostatic force ( I AM NOT SURE ABOUT TRANSLATION SO I AM SORRY, BUT EASILY m*g= (density)*g*h )

for the C i am not sure i dont want to go and open note
and i have a question, how would you like to have shit like this posted on fj, explanations and shit, straight from school lectures and shit transferred to FJ? one day you could say you spent all day on FJ but you weren't procrastinating but actually studying.
#4609 to #4608 - bwiedieter (06/03/2015) [-]
First of all, thanks for the elaborations, I wouldn´t really have known how to tackle this.
Secondly, I don´t know why you continuously apologize for you oh-so-bad English, as it´s nearly spotless.
<-- see left for an answer to your last point. Personally, I´d love that. But I don´t know if there are enough like us around FJ to get you very far in terms of thumbs. Should you do it at one point, please mention me for shits and giggles and my educations sake ;-)
#4610 to #4609 - anon (06/03/2015) [-]
its not about thumbs , is there exact subject you would like to see? I would plan to start from basic shit and then add more. But if there is something i could help with right now, i'll gladly do it. I could cover field of chemistry engineering of plastics. But only to extend to my knowledge that is knowledge of someone in 2nd year of uni.
#4613 to #4610 - bwiedieter (06/03/2015) [-]
Oh and as a general field, Astronomy would be my absolute favourite. Maybe we should do a collaboration here? Just know that I lack the skills to make visually appealing content, I have never used editing software of any kind
But think of how cool that would be: Educating FJ with peculiar problems out of all the scientific fields. One day they´d learn something about astrophysics, next day game theory, next day material sciences, next day quantum theory etc etc...
#4612 to #4610 - bwiedieter (06/03/2015) [-]
Regarding Chemistry: Why do chunks(!) of alkali metals explode in water, instead of just getting really hot? A reaction can only happen on the relatively small surface area of the chunk (as opposed to the big surface area with a powder), so the reaction should always be comparatively slow and steady. But that´s not what happens: The chunks fizzle for a tiny bit, and then all of a sudden violently explode!
And they explode even in a vacuumized water container, so it´s not the Hydrogen exploding (which would need Oxygen to react). It has to be the exothermic character of the reaction.
On top of all that, the Leidenfrost Effect should seperate the chunk of hot metal and the surrounding water with a layer of metal gas after the temperature difference gets big enough, which should slow down the reaction even further, maybe even to the point of pretty much halting.
So: Lots of reasons why chunks of alkali metals in water should guarantee a realtively slow, steady reaction. And yet, exactly the opposite is reality - as anyone who has ever seen one of these reactions happening can attest.
This puzzles me. Do you have an idea? Because I´m stumped here.
User avatar #4634 to #4612 - nought ONLINE (06/06/2015) [-]
even with small surface area they react so violently to water that so much hydrogen gas is generated and combust
for the vacuum I am guessing the rapid increase of temperature and production of H2 alone is enough to explode
idk about everything else
#4619 to #4612 - anon (06/06/2015) [-]
ou, sorry for late answer, so i didn't look at it but i think that it is not metal that explodes itself, you see alkali metals are highly reactive and they are bonding with oxygen and releasing hydrogen, and the explosion is produced with that hydrogen. As I said, i did not look into it, but this is what i think that happens.
#4620 to #4619 - bwiedieter (06/06/2015) [-]
Nah, bruh. That´s the thing. Alkali metals don´t need Oxygen to do their exploding. And a Hydrogen explosion DOES need Oxygen.
Can´t really be the Hydrogen then, can it?
Anyway, riddle me this, I´d love if you had an answer ;-)
#4621 to #4620 - anon (06/06/2015) [-]
2 Na + 2 H2O → 2 NaOH + H2, so the hydrogen which is made from this reaction is in gas form and the heat of the exotermic reaction is enough to ignite it. firstly i thought it was beacause reaction of hydrogen and oxygen but i reread your comment saying it burns even in vacuum. So it must be this, or its witchcraft and even if you look at it from different view what else could it be? i hope this satisfies you
#4622 to #4621 - bwiedieter (06/06/2015) [-]
"so the hydrogen which is made from this reaction is in gas form and the heat of the exotermic reaction is enough to ignite it."
Well, not really convinced. While what you wrote is true, each H2 still needs one O to burn. And that is really the point I don´t get
You know what i mean, it´s in a vacuumized container PLUS completely submerged in water. And even if there is residual O in the container/ underwater, this gets used up in the very first second or two of the reaction.

I´m just really stumped here, and I can´t find anything via Google, and I can´t reach my old chemistry professor.
I´ll just leave this thread here in case a wonder happens and someone working in the field reads this.
But thanks for your time man! Appreciate it!
<-- Internet High Five!
#4625 to #4622 - anon (06/06/2015) [-]
ok i found something, i will translate it. ...after electrones transfer from alkali metl to water, metal gets huge positive charge. That charge is so big, that it overcomes surface tension of metal, ripping it apart. This expresses with creation of metal "needles" which very quickly are penetrating to surrounding water. This enlarges surface for reaction and reaction can start.... there is also a video of it from ultrafast camera but i have to find it yet. This discovery as stated in article was done by czech and german scientist. The article is form 27.1.2015. thus its pretty young.
#4627 to #4625 - anon (06/06/2015) [-]
www.youtube.com/watch?v=egPghR_toWA this is the video and in its description was this article in english www.rsc.org/chemistryworld/2015/01/alkali-metal-explosion-explained, i am going to read it just now .... i hope this answers your question completly. I AM NOT THE KIND OF PERSON WHO LEFTS QUESTIONS UNANSWERED. .......... but still i somehow feel this wont be enough, you wanted to know how it does without presence of oxygen right?
#4626 to #4625 - bwiedieter (06/06/2015) [-]
You absolute madman. Thank you bro! If that vid lets me actually see this shit happening, I´m creaming my pants.
#4628 to #4626 - anon (06/06/2015) [-]
www.youtube.com/watch?v=egPghR_toWA this is the video and in its description was this article in english www.rsc.org/chemistryworld/2015/01/alkali-metal-explosion-explained, i am going to read it just now .... i hope this answers your question completly. I AM NOT THE KIND OF PERSON WHO LEFTS QUESTIONS UNANSWERED. .......... but still i somehow feel this wont be enough, you wanted to know how it does without presence of oxygen right? re commenting for your notification
#4629 to #4628 - bwiedieter (06/06/2015) [-]
Yeah, you´re correct about that last point... However, you´ve already cleared up A WHOLE LOT of stuff for me, dude!
#4632 to #4631 - bwiedieter (06/06/2015) [-]
Hey, I´m naturally curious. If you say deeper, than deeper it is. close your eyes and think of home, I´m going deeper.
#4633 to #4632 - anon (06/06/2015) [-]
**anonymous used "*roll picture*"**
**anonymous rolled image** no need to think about anything i like it rough. and if you excuse me for a moment (more like several hours) there is playlist of 12000 song which has got fucked up and needs my atention. [and also games]
#4630 to #4629 - anon (06/06/2015) [-]
no problem mate, we just need to go deeper
#4581 - phanactssonjoe (05/28/2015) [-]
If I plant like a bunch of cherry seeds to grow a cherry tree, will it grow into a huuuuge cherry tree? assuming all of them would sprout and grow into one tree or what
User avatar #4598 to #4581 - nimba (06/02/2015) [-]
no
User avatar #4580 - optimussum (05/27/2015) [-]
someone explain quantum mechanics to me like im 5 pls
User avatar #4653 to #4580 - gmarrox (06/10/2015) [-]
Sometimes stuff isn't stuff.
User avatar #4579 - charizarddad (05/27/2015) [-]
1st question is basically how do solar panels work. Suppose I am generating 15 watts per solar panel at 3 panels, so 45 total(duh) and storing it into a battery 12v 35AH(specifically for solar applications) battery. How does that work? Do the solar panels just store the power into the battery when available? And at watt rate geddit ? 45 watts per second? Minute? Or? I also do not know a whole lot about electricity, i know terminology but not really how it works.

So then next question i guess is how does the battery work and how do appliances draw power? This is also where i get confused. Lets say in this situation i am using a computer and the psu is drawing 500 watts of power. Could i even hook the battery up to the psu? Would it run it, and for how long?

Lets say this is in perfect conditions for arguments sake, the psu is at 100% efficiency and the solar panels are drawing the max they can(45 watts.)
#4606 to #4579 - bwiedieter (06/03/2015) [-]
1. Do you mean Solar Panels or Photovoltaics? There is a big difference between the two, and what you describe sounds a lot like Photovoltaics.
2. A Watt is defined as joule per second.
3. It always helps if you visualize an electric current as water flow, and the cables as tubes filled with water. additionally, the negative pole can be visualized as a pump, electricity always goes from - to +. Maybe this helps you a bit already, I know it helped me when I was faced with electricity problems.
User avatar #4574 - sweetbutteryjesus (05/26/2015) [-]
How do I find an entropy value?
All the vids on youtube aren't explaining where I find them.
#4576 to #4574 - zanntaggerung (05/26/2015) [-]
You'll need to be a little more specific than that, but from what I remember of chemistry (and some quick googling) standard values of entropy S are usually given in tables along with values of standard enthalpy change ΔH to calculate the Gibb's free energy change ΔG using the formula ΔG=ΔH-TS (T is the temperature in Kelvins). This is done for each of the reactants and products, summed up for both sides and then do products minus reactants to find the overall ΔG.

Hope that was some help, entropy values aren't normally asked to be found unless you're given ΔG and ΔH so you could just solve the equation for S.
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#4573 - minorian has deleted their comment [-]
#4567 - phanactssonjoe (05/25/2015) [-]
i wish i had a atom smasher where i can take all of the molecules and atoms from a physical things, accelerate it, and shoot it at stuff. like it would seperate all the molecules and atoms of my old latop and shoot it at a car
#4565 - anon (05/25/2015) [-]
How do I solve this? It's says: "Solve the equation system."
User avatar #4582 to #4565 - dalokan (05/28/2015) [-]
Is it slope intercept form?
User avatar #4578 to #4565 - rubiksdodecahedron (05/26/2015) [-]
Add the equations together to get 3x=9, the y's cancel out divide to get x=3, perform some simple substitution and basic math to get y=9.
#4575 to #4565 - zanntaggerung (05/26/2015) [-]
Excuse the poor quality paint drawing, but one way to do it is to show how y relates to x from one equation and then plug it into y for the other equation so you can solve it for x. Then you can plug the value of x into either equation (I plugged it into the first) and solve for y.
#4577 to #4575 - anon (05/26/2015) [-]
Yes, this is it. Thank you so much!
#4568 to #4565 - phanactssonjoe (05/25/2015) [-]
x = 3 y = 9
#4570 to #4568 - anon (05/25/2015) [-]
I'm sorry, but that doesn't really help me. I need to know the procedure to how to solve the system, and not just the answers. Could you just simply show, how you came to answers, if that isn't too much to ask?
#4571 to #4570 - phanactssonjoe (05/25/2015) [-]
idk how to show how i got the answer beside 3+ 9 is the only one that fits
#4572 to #4571 - anon (05/25/2015) [-]
I'm preparing for an exam, so I just need to know how to solve it, but thanks anyway.
#4566 to #4565 - anon (05/25/2015) [-]
It says**
User avatar #4560 - sweetbutteryjesus (05/24/2015) [-]
What the balls is reaction energy and reaction kinetics
#4561 to #4560 - paintskillz ONLINE (05/25/2015) [-]
In short, it's what says whether a reaction will occur spontaneously or whether energy will be need to be added usually through heat for the reaction to occur.

pls enjoy my completely legible mouse-writing
User avatar #4562 to #4561 - sweetbutteryjesus (05/25/2015) [-]
Does this have to do with Gibb's Law?
User avatar #4563 to #4562 - paintskillz ONLINE (05/25/2015) [-]
Yeah pretty much, however reaction kinetics takes things a step further and is used to determine the probable mechanism that a reaction undergoes in order for it to occur. That's something you shouldn't expect to see til advanced college level chemistry though
User avatar #4564 to #4563 - sweetbutteryjesus (05/25/2015) [-]
Okay, thanks.
I literally have no idea what I'm doing and finals are coming up.
#4559 - phanactssonjoe (05/24/2015) [-]
why are fresh cherries so expensive? they have rainier cherries for $8 a pound and these other ones for $6. just wondering if theyre harder to grow or something
User avatar #4557 - PVTDickStryker (05/23/2015) [-]
Why cant eye color be yellow or orange, and why cant hair be silver, green or blue?
User avatar #4558 to #4557 - subtard (05/23/2015) [-]
Wikipedia says people can have a light or dark blue epithelium at the back of the iris and varying amounts of yellow to brown melanin in the front. So blue eyes are from little melanin so all you see is the blue epithelium. Green is from blue epithelium and yellow melanin. Brown is when there's a lot of brown melanin. Even explains hazel/amber eyes and all that.
Hair color is from two types of melanin called eumelanin and pheomelanin which are brown/black and red. So varying levels of these create all hair colors.
So our bodies would need to use a totally different process to create different pigments and use them instead of melanin in order to have wonky hair/eye colors.
#4569 to #4558 - phanactssonjoe (05/25/2015) [-]
i was always curious if humans had a stronger version of chlororphyll in our hair so we can get enough energy from sun. we would still food but just thought it would be cool
User avatar #4556 - fjtv (05/18/2015) [-]
I am doing an experiment which includes microwaving small amounts of iron oxide, is it dangerous to microwave it? I figure it might be, since iron oxide is made of, well, metal and oxygen. We all know metal shouldn't be put in a microwave, what about a metal oxide?
User avatar #4555 - xXMAQXx (05/17/2015) [-]
anyone want to help me with legendre equations?
User avatar #4554 - lulzforalpsplane (05/17/2015) [-]
https://youtube.com/devicesupport ....wut...
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#4551 - phanactssonjoe has deleted their comment [-]
User avatar #4549 - sphincterface (05/15/2015) [-]
Alright guys so brace yourselves. This is something that has pissed me off immensely and I need to vent. So some person on Facebook posted this link to some stupid article involving Amish people. Supposedly, according to this one article, Amish children have lower rates of autism. Do you know what the article pointed to after this? You probably guessed it by now. It claims that it has a connection to the fact that the Amish don't vaccinate. The ignorance of some people is just fucking stupid.
User avatar #4553 to #4549 - subtard (05/16/2015) [-]
Just as conclusive as saying building barns prevents autism
#4550 to #4549 - smudgiemuffins (05/15/2015) [-]
Honestly, I wouldn't say it's so much ignorance. I don't think this people are truly convinced that vaccines cause autism. I think it's rather that they don't care. The actual truth of the matter is completely unrelated to their goal. I suspect the real goal is socially driven. Humans just like to feel like they're fighting for something. They like conflict in their lives. And what better conflict than this? You've already got the archetypical scary green chemicals and mean scientists. You're not doing anything overtly illegal so no one can actually do anything to stop you. You're hurting people only indirectly so you don't have to take responsibility for the consequences.

At the end of the day, I don't know how to deal with people like that. Education is the best way to fight ignorance, but like I said, I don't think this is ignorance in the normal sense.
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