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Could you guys please share your best resources for me to learn electricity and electronics? I'll be eternally grateful to you all.
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>>8975251
Theres literally an entire wikia on the matter.
http://4chan-science.wikia.com/wiki/Electrical_and_Electronics_Engineering
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>>8975255
Oh, sorry, I didn't know about this. I'll give it a read. Thanks a lot!
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>Circuit Theory
start with that
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I'm gonna soon have an interview soon and some of the questions will be about stats
I don't have any formal stats training, so I was wondering if there's a good resource ( short book maybe) that walks me through concepts such as
>non-parameteric tests
>confidence intervals
>significance testing (fisher vs other method)
>etc
Basically stuff that can come up in quiz-like interviews. I already know stuff like probability, regression, bayesian stats ("machine learning stats") but not the more traditional ones.
Pls help, rn I'm just reading the wikipedia pages but I feel like there must be a more systematic approach (also ideally I'll learn everything today)
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How much truth is there to the alleged link between animal protein consumption and cancer? I had testicle cancer before, and the thought of losing my remaining nut terrifies me about as much as I love red meat.
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>>8975135
Eating red meat increases your risk of colorectal cancer.
This is just a fact at this point.
Now, the risk goes up by a negligible amount compared to the risk of getting lung cancer because of cigarettes but still, it's carcinogenic.
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I'm trying to wrap my head around radio carrier frequencies and data transmission rates.
For analog signals, they can have a carrier frequency.
From what I've picked up, the carrier signal must be greater than the passband width of the analog signals being sent. And the data transmission rate is proportional to the frequency of the carrier signal. So higher frequency carrier signals = more data transmission = more bandwidth of original signals being transmitted.
Is this correct? Why is the carrier signal frequency proportional to the input bandwidth?
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Who else thinks there should be an astronomy dedicated board?
it's part of science i know but i see a lot of astronomy posts and personally i consider it as a subject worthy of a proper board.
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This board is already slow as thick shit through a funnel, no need to split it up further.
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>>8975110
there will never be an /ast/ board because itd be flooded with flat earth threads. the only reason sci is so slow is because mods delete everything scientific that explores the flat earth.
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>>8975110
Nobody ever talks about astronomy.
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Aero Eng question.
Why is the flow through a jet/rocket engine considered isentropic when combustion occurs?
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>>8975093
It is not, however as a first approximation you can assume it is for some rough values.
In reality, every component has an "adiabatic efficiency". On a temperature-entropy diagram, the non-ideal components will have curved lines instead of going straight up or down when changing temperature. Adiabatic efficiency of a component allows you to characterize how this increase in entropy translates to the T-s diagram and subsequently the effects on pressure ratio etc.
Furthermore, every combustion chamber has a "pressure ratio" across it in the 0.9-0.98ish range which describes the loss in stagnation pressure compared to the stag. pressure that would be achieved if processes were isentropic.
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>>8975093
>>8975106
Was just about to stride in and put on my aero eng pants but this guy gave a pretty good explanation, kudos.
Basically, isentropic efficiency is the maximum that isphysically possible, with no heat losses, bleeds, efficiency losses due to pumps, bearings and flow friction etc etc etc. It gives a good first approximation to know what your ceiling will be, and takes relatively little time to calculate. Relatively.
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What would happen if you were to drop cesium into liquid oxygen?
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>>8975048
Serious question guys, has such an experiment ever been documented? I've tried researching but haven't found a trace. I can only speculate, but more indepth look at it would be better.
bump
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>>8975048
what would even be the point of such an experiment? What do you want to observe? Probably nothing very interesting would happen you'd just get cesium oxide forming. Maybe it gets hot? Why do non-chems always think of the most mundane 19th century-tier experiments to perform?
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We have a multivariable (2 variables) parameter which has a (asymptotically) multivariate normal distribution, with known mean and covariance matrix.
How do we find the confidence interval for just one of the two variables?
Do we need to incorporate covariance?
e.g (a,b) ~ N(0,\Sigma)
Is the confidence interval for a:
[math]a = 0 \pm 1.96* \Sigma_{1,1}[/math]
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Confidence intervals don't make sense in 2D, use confidence ellipses instead.
Also >>8969578
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Ok /sci/ i have a problem.
I'm going to have some sort of discussion with a friend about space exploration. And when I stopped to think of his stupidity to think that the space exploration does not work, I asked myself: "Is it just stupid that some people or someone important thinks the same?"
Do you know of a case in which some important person has said that?
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>Healthy young child goes to doctor, gets pumped with massive shot of many vaccines, doesn't feel good and changes - AUTISM. Many such cases!
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>The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive.
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>It’s freezing and snowing in New York – we need global warming!
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i had a final exam today and one question was:
if you have a 1m wide box positioned 1 metre away from a camera and another box which is 2m wide at a distance x from the camera and both boxes have a width that appears equal in length in the snapped image, then what is the distance x?
the camera has a focal length of 1m.
i answered 2 meters. was i right?
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>>8974992
>the camera has a focal length of 1m.
Not what I would have chosen for a subject 1m away,
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,
I'm trying to race my friend in a mile race on the track. How would i set it up so that we each run the same distance while staying in our own lanes the whole time? (His mile time is like 4:55 too and i do sprints like 400m, so tips would help :)
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>>8974926
A track usually have marks that show the starting position
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http://www.livestrong.com/article/168904-what-is-the-distance-around-a-running-track-for-each-lane/
>Since the IAAF has standardized track lane widths at 1.22 meters the above formula calculates the distance around the track in lane 2 as 407.67 meters, lane 3 as 415.33 meters, lane 4 as 423 meters, lane 5 as 430.66 meters, lane 6 as 433.38 meters, lane 7 as 446 meters and lane 8 as 453.66 meters.
I'm sure you could work it out from this, but if you take the lead how will you know if your rival stays in their lane?
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>>8974926
for the mile you start staggered and then you're free to roam after the first line, whatever it is called
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I am immensely intrigued by recent studies into the health benefits of NAD+. I have read that it reverses aging, cures addiction, and has a dramatic impact on mental clarity and cognitive ability.
Has anyone here undergone an IV infusion of this? I am considering it as there is a clinic offering the service that is only 1 hour away from my home.
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i prefer rectal administration of semen, it also reverses aging, cures addiction, and makes you a genius, but on top of that it cures cancer.
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>>8974786
its useless
you know what truly gives those benefits?
>exercise, sleep, healthy diet, good hygiene
common sense you retards, there are no magic pills
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i bet it cures cancer too
Anonymous
Amazingly, there's no thread in /tv/... 2017-06-14 05:48:40 Post No.8974691
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Amazingly, there's no thread in /tv/... 2017-06-14 05:48:40 Post No.8974691
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Amazingly, there's no thread in /tv/...
Anonymous
2017-06-14 05:48:40
Post No. 8974691
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Dude was not only a genius, but also a total Chad Thundercock...
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>individuals placed tentatively under homo sapiens (archaic not specified) or even homo helmei have modern features, yet are much older than originally thought
>"ORIGINS OF MAN PUSHED BACK 100,000 YEARS, OLD THEORIES DEMOLISHED!!1!"
Why is this shit allowed? I feel like they jumped the gun a bit.
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Bump
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>>8974566
not sure if you're ripping off my thread from a simplified perspective, but im glad you are asking a good question in terms of how journailsm use science to force public acceptance of conclusions which are often wrong
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There is an enormous difference between actual scientific journalism and SCIENTISTS JUST DISCOVERED X AND ITD BEAUTIFUL brainlet clickbait trash. Just lile between you and an intelligent OP.
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Since every object with mass in the world has some form of magnetic field, would it be possible in the future to create a device that produces that exact opposite magnetic field so the object no longer has a physical collision? Am I insane?
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Are you the same guy who's been making shitty threads over and over again? Please stop.
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>>8974348
No you aren't insane and what you're talking about right now is how anti gravity works. However you have to understand how a magnetic field works and what moves it (yes it is driven by something that would take hours to explain and it is the "opposite" of a magnetic field). The Dielectric plane is the centripetal force that drives magnetism and controls how large the magnetic field will be via induction, The faster the induction, the smaller (but stronger) the magnetic field.
Think of a pulley and a really lose belt, where the pulley is the dielectric plane and the belt is the magnetic field it'll flop around when the pulley is going slow, but once it gets up to speed the centrifugal force will straighten it out. The tighter the belt, the more power can transmit from the pulley and the less space the belt will take up.
TL;DR: Pierce the heavens with your dielectric drill.
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Magnetism has two poles: north and a south.
For antimagnetism you'd also need two poles: east and west.
Because the earth rotates we only have the north and south poles. To get antimagnetism you'd need East and west poles, or a world that revolves top to bottom.