Well, an old puzzle my father and I were trying to solve. It was a bonus question from my physics class last year but I can't remember the solution.
A skier of mass m is on a snowball of radius r. He begins to slide down the snowball, at what angle does he lose contact with the snowball?
45 degrees
>>8194615
360 degrees sempai
GRAVITY IS PULLING HIM DOWN NO MATTER WHERE HE IS ON THE SNOWBALL, HE HAS NO INWARD ACCELERATION, HE LOSES CONTACT AT 90 DEGREES IF NORTH IS 0.
so I've been thinking about how fiction other than star wars rationalizes the idea of lightsabers actually working
the usual problem that arises when thinking about how to make one that actually works (using just a high-powered laser for a blade, not contained plasma) is "the blade will never end"
but is it impossible to contain a laser beam? could you not potentially build some kind of containment unit to cap the blade, with a photovoltaic system to reduce energy loss?
>>8194606
I've thought about this.
IF you could get a high enough power laser, you could have a small bar run parallel to it, with a lens on the top. The lens(or set of lenses) would be concave(toward the laser) and refract the light, spreading out the beam over a large area so it is virtually harmless.
Of course, nobody wants a metal beam on their light-saber. But that's the only practical way I see.
>>8194636
the laser blade literally is extendable. Why not just have the laser surround the metal bar, and the energy is obviously so concentrated you can't see through it, so the bar in the center is concealed? As it extends, the blade grows in length
>>8194705
picatar relatid
>all processes are reversible
Is this the worst science meme?
If you write something on a paper then burn that paper and disintegrate the remains with a blast of water no amount of effort will ever retrieve what was written on that paper.
>>8194110
>big crunch
/thread
>>8194110
>all processes are reversible
Whoever says this should kill themselves, then reverse the process.
>>8194110
I really don't think they meant physical processes
How close are we to immortality and putting brains in robots really? I find very mixed answers about both.
Hypothetically, what would become of us if we just kept breeding and we all were immortal? Would we phase out breeding almost entirely and the same few billion people would continue living forever?
Sorry if this sounds like x-tier, uneducated garbage, but I'm actually curious about it.
>>8193947
>How close
When you will be at the end of your life, we will start to make the richest of us immortal. You won't make it.
>I find very mixed answers about both.
What are you expecting from /sci/?
>we just kept breeding and we all were immortal
Human hunting seasons
>>8194129
Well, I moreso meant I find mixed answers when I'm doing my own studying on the subject.
A lot of contradictions and baseless conjecture both ways
Not very. Realize the brain is dependent on a lot more from the body than just nutrients and oxygen. If you think otherwise, then cut out your thyroid, castrate yourself, and cut the adrenal glands off your kidneys. Then remove ~70% of your liver and induce scarring where your CSF drains.
Also, remove all your adipose cells, see how readily you can tell you're hungry. Also, adipose makes estrogen, which men need to an extent as well.
Etc. It's a ways off, if viable at all.
Does phenotypic variation exist between humans? If so, What role does it play in modern day evolution?
Yes.
You'd have to be blind not to notice phenotypic variation between humans.
>>8193810
No all 7 billion human beans look exactly the same.
Are you retarded?
Hello /sci can you give me any recommendation of books for basic electronics, im studying electronic engeeniering
>>8193513
The Art of Electronics - Horowitz and Hill
>>8193519
This. Heard it's the best biik around for electronics.
>>8193513
Our name is /sci/, get it right, newfag.
fixing co2 and methan (number 1 greenhousegas)
by fixing overpopulation. helping the nature to rebuild.
1) send rocket to asteroid-belt
2) rocket has robot who equips asteroids with little rocket engines
3) send asteroids to earth and let it go down on india & co
pros:
+ they would never figure out what or who hit them
+ maximum devastation
+ no radioation
+ its bio
cons:
?
any cons /sci?
no not my anime
>>8193426
If you can leave the rest unharmed, then yes
Nuclear winter is not good for animals and plants (food)
>>8193426
Who would man our call centres and provide technical support for retards?
hey /sci/
got a bug here i am not sure what it is, found a few crawling on a wall
asked about bugs here a few years ago so hoping you can help again!
Put a magnifying glass on it under direct sunlight to see it better.
>>8193404
it's wallbug
>>8193404
it is a penny you dimwit, just let it go and it will fall from the wall
Dear 4chan users,
try to find me with the message hidden in this image. We expect the message of a few curios individuals.
Greetings,
TheTowers
>>8193280
You're a gorilla, aren't you?
>>8193280
I'm not very curios, but I sure am curious.
Is the monkey going to use my banana as a banana?
Might this be real, /sci/?
>>8193202
Did you make this diagram yourself?
Because it doesn't make any sense.
Yep, it's one proposed possibility, but no one knows for sure. Another possibility is the heat-death of the universe, where the universe keeps expanding until nothing collides any more and everything is "dead" (ie. no further interactions at all).
But again, no one knows-- it's one of the great mysteries in physics.
>>8193202
No. The universe will continually expand forever, as far as we know.
http://map.gsfc.nasa.gov/universe/uni_shape.html
Are nanobots a possible thing that can happen or should we just call them cells at that point?
pls respond
>>8192854
Are you asking if people should call nanobots "cells" when they do not meet any of the structural criteria for actual being a "cell"?
It's 2016. It's time to admit it.
Do Black Holes really exist /sci/?
https://www.strawpoll.me/10702671
>>8192706
Amazing Atheist moving on to a new meme?
>>8192706
Is that Meth? Looks like Meth must be meth
>>8192706
Yes, because it's a well substantied, unfalsified hypothesis. Karl Popper don't lie.
Has this helped you?
>>8192571
It definitely kept me busy
>>8192571
Regardless of whether it did, the practice is better than no practice for developing an intuition.
Yes for physics
Post the best telescopes in the market. (Post the sites that you can buy them). And,if you want,show a picture of your.
any dobsonian is the best telescope in the market
as you increase its size, it becomes better and better
aperture >>> all
any 12" dob will destroy even the most expensive non-dobsonian telescope, regardless of what it is
and a 16" or greater dob is god-tier, you will be worshiped
Following. I'm thinking about buying one, but have no idea whats what
>>8192538
So if I have an excellent view from my balcony, I can stare into far away apartments, yes?
How much correlation do we need in order to establish a causation?
The Bradford Hill criteria, otherwise known as Hill's criteria for causation, are a group of minimal conditions necessary to provide adequate evidence of a causal relationship between an incidence and a possible consequence, established by the English epidemiologist Sir Austin Bradford Hill (1897–1991) in 1965.
The list of the criteria is as follows:
Strength (effect size): A small association does not mean that there is not a causal effect, though the larger the association, the more likely that it is causal.[1]
Consistency (reproducibility): Consistent findings observed by different persons in different places with different samples strengthens the likelihood of an effect.[1]
Specificity: Causation is likely if there is a very specific population at a specific site and disease with no other likely explanation. The more specific an association between a factor and an effect is, the bigger the probability of a causal relationship.[1]
Temporality: The effect has to occur after the cause (and if there is an expected delay between the cause and expected effect, then the effect must occur after that delay).[1]
Biological gradient: Greater exposure should generally lead to greater incidence of the effect. However, in some cases, the mere presence of the factor can trigger the effect. In other cases, an inverse proportion is observed: greater exposure leads to lower incidence.[1]
Plausibility: A plausible mechanism between cause and effect is helpful (but Hill noted that knowledge of the mechanism is limited by current knowledge).[1]
Coherence: Coherence between epidemiological and laboratory findings increases the likelihood of an effect. However, Hill noted that "... lack of such [laboratory] evidence cannot nullify the epidemiological effect on associations".[1]
Experiment: "Occasionally it is possible to appeal to experimental evidence".[1]
Analogy: The effect of similar factors may be considered.[1]
>>8191690
Has this all been verified for "man made" climate change? Not trying to be /pol/ here, just a curious layman question.
>>8191690
>Temporality: The effect has to occur after the cause
But doesn't special relativity posit that there is no absolute time? So you cannot impose a temporal order on events.