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Thursday, December 8, 2016

What happens to the molecules containing radioactive isotopes when the atoms decay?

What happens to the molecules containing radioactive isotopes when the atoms decay?

What happens to the molecules containing radioactive isotopes when the atoms decay?

Posted: 08 Dec 2016 05:00 AM PST

I'm a chemistry major studying organic synthesis and catalysis, but something we've never talked about is the molecular effects of isotopic decay. It's fairly common knowledge that carbon-14 dating relies on decay into nitrogen-14, but of course nitrogen and carbon have very different chemical properties. The half life of carbon-14 is very long, which means that the conversion of carbon to nitrogen doesn't happen at an appreciable rate, but nonetheless something has to happen to the molecules in which the carbon is located when it suddenly becomes a nitrogen atom. Has this been studied? Does the result vary for sp3, sp2, and sp hybridized carbons? Does the degree of substitution effect the resulting products (primary, secondary, and so on)? I imagine this can be considered for other elements as well (isotopes with shorter, more "studyable" half-lives), but the fact that carbon can form so many different types of bonds makes this particular example very interesting to me.

submitted by /u/IanTheChemist
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If color is the non-absorption of specific wavelengths, wouldn't a 'red' laser consist of every color except red?

Posted: 08 Dec 2016 06:33 AM PST

Normal stars are made out of hydrogen which undergoes fusion. Can I make a star out of any element, provided I have enough mass to fuse that element? Say, Iron?

Posted: 07 Dec 2016 08:25 AM PST

An addition, I am aware of the "iron peak", so what about an element lighter than iron but still not helium or hydrogen?

submitted by /u/labtec901
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Do Godel's Incompleteness theorems currently have use whatsoever in Physics? If not, might they some day?

Posted: 08 Dec 2016 04:41 AM PST

I am plowing through Godel Escher Bach for the second time at the moment (amazing read) and I was curious as the what connection (if any) the strange incompleteness of formal systems has with the physical universe.

submitted by /u/godelbrot
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If we could synthesize antibodies could we use them to treat immunocompromised people?

Posted: 07 Dec 2016 11:10 PM PST

Let's say we manage to find a process to duplicate antibodies, could we make a whole bunch of them and inject them into a patient to help the immune system fight the infection?

submitted by /u/FatGecko5
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Why could I hear the pilots radio comms through my noise-cancelling headphones?

Posted: 08 Dec 2016 01:20 AM PST

I fly quite a bit and I always wear my noise cancelling headphones when I do. But this morning while we were waiting to take off I could hear the pilots radio communication coming through.

I was listening to music on my phone (on flight mode), and I can't figure out the mechanism which would allow the radio comms to be picked up...

I tried turning off the noise cancelling and it appeared to stop, but he might have just stopped talking - it's hard to tell.

submitted by /u/rabbyt
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What makes cling wrap clingy?

Posted: 07 Dec 2016 05:07 PM PST

Does hot antimatter glow with antiphotons?

Posted: 07 Dec 2016 06:46 PM PST

So, if we heated a bar of anti-iron up so it was glowing with blackbody radiation, would the photons be antiphotons and would they collide with photons to eliminate each other .... and if they did would they become energy since photons are already energy?

submitted by /u/ChocolateBallSack
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According to the CDC, "There is one suicide for every estimated 25 suicide attempts." and, "There is one suicide for every estimated 4 suicide attempts in the elderly." Why the difference?

Posted: 07 Dec 2016 02:39 PM PST

Is it just physical frailty, access to deadly prescription medication, life knowledge, etc? Is it known why there is a higher success rate among the elderly?

submitted by /u/lavenderfart
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How would it feel to dive into a mafic lava flow?

Posted: 08 Dec 2016 03:58 AM PST

How long would you live for?

submitted by /u/cashewtrailmix
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How are we able to observe Earthrise from the moon if the moon is tidally locked with Earth?

Posted: 08 Dec 2016 05:47 AM PST

I was thinking of an Earth rise conceptually; wouldn't the Earth stay in one spot in the moon sky because the moon is tidally locked to Earth? I saw this .gif and now I'm wondering if the moon isn't perfectly tidally locked or if the video was taken during ascent/descent.

submitted by /u/Avenged_Bear
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Since black holes destroy all matter, including photons, does that mean that the coldest parts of the universe are black holes?

Posted: 08 Dec 2016 05:24 AM PST

AskHistorians is holding an AMA on Medieval Automata, come check it out!

Posted: 07 Dec 2016 07:43 PM PST

Looking at Cassini's latest Saturn images, is there any way of knowing /guessing (for a layman) how deep/high certain cloud layers are?

Posted: 08 Dec 2016 03:58 AM PST

Image in question is "Over Saturn's Turbulent North", posted on December 6, 2016.

I'm having a hard time picturing anything other than a flat, beautifully marbled cloud "surface". Is it possible to measure / guess at how deep certain cloud banks are (aka "the white, whispy clouds are .... km high, lying on darker bands of lower clouds, made up of...") and what they would look like if one where to fly through them (something like this image posted on ircamera.as.arizona.edu).

submitted by /u/iBreak140
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is there any limit to how big a supermassive blackhole can be (size/mass)? what is the biggest we have found yet?

Posted: 08 Dec 2016 03:25 AM PST

Are there some good alternative explanations or hypotheses in place of the dark matter theory?

Posted: 07 Dec 2016 07:43 PM PST

The fact that something like dark matter exists in such a large quantity that is yet undetectable seems less likely to me than an alternative explanation like, maybe the laws of physics act differently in space in different places or this extra mass I see made up of a bunch of tiny black holes everywhere

submitted by /u/dkschrute79
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Why does Aluminium-to-Aluminium has a higher friction coef than other metal-to-metal systems?

Posted: 08 Dec 2016 06:02 AM PST

Based on this information, it seems as if aluminium to aluminium has a higher friction coefficient than copper to copper, iron to iron, and teflon to teflon.

Such that Al to Al has a higher friction than both softer/weaker and harder/stronger materials, which throws me off as there does not seem to be a clear pattern?

How does copper on copper, and iron on iron, have the same friction coefficient, given their vastly different properties?

How does material affect friction after all?

submitted by /u/Ne_Oublie
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Is the shape of a popcorn kernel more predictable than the shape of a snowflake? If so, why?

Posted: 07 Dec 2016 08:45 PM PST

What limits planet spinning speed? How fast planet is able to spin?

Posted: 07 Dec 2016 09:18 AM PST

So for example how fast planet with earth size and mass could spin?

submitted by /u/M4d4o
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Is a magnet's magnetic field get stronger the smaller it is?

Posted: 08 Dec 2016 01:27 AM PST

Why does it get stronger as it gets smaller? Just because the fields are and can be closer together? If so, If I could print a magnet what would happen if I print them in a spiral or coil? Would the fields combine?

Edit 1: Not sure if this belongs in physics but seemed like the best choice.

submitted by /u/Exquisite_Death
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Can animals see the stars?

Posted: 08 Dec 2016 12:25 AM PST

Humans can see under good circumstances maybe 6000 stars. Have other animals this capability? My guess is not too many. Can we count ourselves lucky to be able to experience this sight?

submitted by /u/shele
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How were heavy elements formed?

Posted: 08 Dec 2016 12:12 AM PST

Can someone give me a semi-layman's explanation on the formation of heavy elements? I know that metals such as carbon and iron can be formed within stars, but how did much heavier elements than those form in the early universe? My original understanding came from a very basic Carl Sagan explanation, but that's not quite comprehensive enough to really explain it to me. Can anyone shed some more light on this for me?

submitted by /u/jimmy_costigan
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Why/how do antidepressants make your dreams more intense and strange?

Posted: 07 Dec 2016 03:26 PM PST

I've been taking lexapro for a few months now and my dreams went from normal and mild, to absolutely fucked up and intense. Why exactly does that happen?

submitted by /u/InfestedBroodlord
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vào lúc No comments:

Wednesday, December 7, 2016

Does the supermassive black hole in the center of our galaxy have any effects on the way our planet, star, or solar system behave?

Does the supermassive black hole in the center of our galaxy have any effects on the way our planet, star, or solar system behave?

Does the supermassive black hole in the center of our galaxy have any effects on the way our planet, star, or solar system behave?

Posted: 06 Dec 2016 08:03 PM PST

If it's gravity is strong enough to hold together a galaxy, does it have some effect on individual planets/stars within the galaxy? How would these effects differ based on the distance from the black hole?

submitted by /u/gotthelatkes
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Why do most experimental fusion reactors focus on deuterium-tritium fusion, and why isn't deuterium-proton fusion ever used?

Posted: 06 Dec 2016 06:37 PM PST

Deuterium-tritium fusion produces a helium-4 nucleus and neutron. In stars, deuterium and protons are fused to create helium-3 without the production of a neutron, in the second step of the proton-proton chain reaction. Wouldn't deuterium-proton fusion be the much better choice, considering they have the same amount of electrical repulsion, wouldn't generate power in the form of neutrons, and are much cheaper?

submitted by /u/Schaefer73
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Why do infants lose certain abilities around 6 months old, such as distinguishing between different language sounds and different primates' faces?

Posted: 06 Dec 2016 10:23 AM PST

Why doesn't the n-body problem make the rotation curves of disc galaxies unpredictable?

Posted: 06 Dec 2016 01:16 PM PST

The difference between the observed and expected rotation curves of disc galaxies is explained by the presence of dark matter.

But how do we even have a predicted rotation curve for disc galaxies?

Doesn't the n-body problem mean the radial velocities of the stars in a galaxy are completely chaotic and unpredictable?

submitted by /u/googolplexbyte
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Could Tokamaks be run in a multi-phase configuration?

Posted: 06 Dec 2016 01:42 PM PST

Tokamaks rely on current in the plasma to produce a poloidal field. Since the toroidal coils can't keep increasing the field strength forever, could tokamaks benefit from being run in a multiphase configuration? Could the decay of one toroidal field drive the production of another?

Are other heating methods sufficient to maintain a toroidal current, or are tokamaks a fundamentally transient configuration?

submitted by /u/fermion1022
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Does the decay energy affect the power output in a betavoltaeic battery?

Posted: 06 Dec 2016 01:40 PM PST

I mean does a low energy beta emitter produce as much power as a higher power emitter? (in a power cell) (if so - why? why can't we use the higher energy electrons better?)

As far as I understood it it isn't the extra electron produced that "becomes" the power but it has something to do with a technology like solar cells? (could we use other materials to capture for instance gamma rays to produce power?)

What happends to the electron later - Does it add to the power output by itself so to speak? (if we just packed a beta emitter inside a metal casing, would the casing get a higher voltage potential from capturing the electrons?)

Are there even vast differences between beta decay energies of different isotopes to begin with? (I'm having some problems finding tables of beta decay energies and are finding weird (what seems like probability) graphs of energies. Cobalt-60 beta decay energy seems to be comparable(-ish) (in orders of magnitude) to carbon-14 decay energies if I understand things right).

I know this is a lot of jumbled together questions, but I guess my main curiosity is the title one.

Thank you

submitted by /u/NickForCabbage
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Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology

Posted: 07 Dec 2016 07:05 AM PST

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Economics, Political Science, Linguistics, Anthropology

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions.

The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here.

Ask away!

submitted by /u/AutoModerator
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Do we calculate time or measure it?

Posted: 07 Dec 2016 05:07 AM PST

Do watches actually measure time or does it calculate it by counting it, Because I've been thinking and until now I haven't found a Scalar physical quantity that can be measured by itself, We usually calculate it from a Vector physical quantity, like how we usually calculate mass from weight, but we can't measure mass by itself.

submitted by /u/Moh_Magdy
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Naked singularities, how can such a concept exist?

Posted: 07 Dec 2016 02:53 AM PST

Trying to wrap my mind around these things gives me a headache, how can a singularity exist without an event horizon? What made people come up with this concept in the first place? I mean, the entire fact that a singularity exists means that it MUST create an event horizon?

It's like trying to imagine the Sun existing without gravity.

submitted by /u/DraumrKopa
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Is gravity uniform regardless of density?

Posted: 07 Dec 2016 05:04 AM PST

Specifically, planetary gravity. Does a planets gravitational pull come from the entirety of the planet as a whole despite say, differences in the geologic layers' density? Or is all of that planets gravity coming together with more gravity generated from certain areas like the core? Am I even understanding gravity correctly that it exists as a whole (uniform) or can gravity be stronger on one side of a planet than the other?

Thank you for your time.

submitted by /u/DaHammy
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How are satellites launched as not to run into each other?

Posted: 07 Dec 2016 02:17 AM PST

With Elon Musk wanting to launch 4,000+ satellites into the atmosphere, how are satellites launched so that they don't collide in orbit? Is there any math or timing and angles done to assure that none of the (currently as far as I can find) 2,271 satellites will remain in orbit indefinitely?

submitted by /u/JackJagOfficial
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Do boiling water in microwave oven kills more bacteria than regular boiling, because microwaves itself kills bacteria too?

Posted: 06 Dec 2016 08:32 AM PST

Are these numbers for the elements in the sun correct?

Posted: 07 Dec 2016 04:01 AM PST

So, there's this site that gives some numbers for the abundance of different elements in the sun. I've seen that list a few times recently, so apparently it's something people go by.

Those numbers can't be right, can they? What struck me was the abundances of iron and neon. There's supposedly fewer neon atoms than iron atoms. However, the neon is written as weighing more, even though a neon atom weighs less than an iron atom. So, this seems not quite right. Or am I missing something?

submitted by /u/ahhwell
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How dark is it outside of solar systems?

Posted: 07 Dec 2016 06:16 AM PST

So basically if I was in a space ship travelling to a different solar system and stopped and went outside of the ship. How dark or light would it be?

submitted by /u/SerPlumtree
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When we look into the night sky what exactly are the bright lights?

Posted: 07 Dec 2016 05:32 AM PST

Are the points of light galaxies or stars? After looking into the hubble deep space image: http://hubblesite.org/newscenter/archive/releases/2012/37/image/a/

It states that there are only galaxies, the clearer ones being closer and the discrepant lights being further away. When we look into the night sky from earth are we looking at galaxies? Or stars? From what I've been researching, it seems like we should only be able to see stars in our galaxy but the Hubble Deep space image can see galaxies. Thanks for any response.

submitted by /u/gripts
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Where does acoustic energy go in a vacuum?

Posted: 06 Dec 2016 04:54 PM PST

In a supernova, it seems that sound would travel for a distance through a rapidly expanding gas cloud. Eventually though, the gas would be too thin for sound to travel through. At this point... What happens? I had an idea that the vibrations would be locked in whatever particle is carrying it, creating friction which would produce heat which could radiate through a vacuum, but I have no idea of the plausibility of this.

submitted by /u/XavierDevadander
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Are there any stars travelling around their galaxy at relativistic speeds?

Posted: 07 Dec 2016 04:30 AM PST

If that's possible what kinds of effects would that have on the star and any planets orbiting it.

submitted by /u/DrRehabilitowany
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How can astrophysicists accurately know what happened a trillion the of a second after the big bang?

Posted: 07 Dec 2016 04:22 AM PST

I'm reading a book by Neil deGrasse Tyson and it is talking about what the universe was like at a specific point (trillionth of a second) after the initial big bang. I'm wondering how one can know so much about such a tiny instance in time?

Edit: title autocorrected to "trillion the" should be trillionth.

submitted by /u/painfulblow
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Compton scattering measurements: What is the physical meaning of integrating over a certain spike in energy spectrum?

Posted: 07 Dec 2016 04:09 AM PST

Hi reddit! Me and my friend are both undergrad physics students who are doing a course in which we have to give a short lecture on Compton scattering based on our own measurements.

With our data we can draw the energy spectrum with y-axis being the number of photons that hit the detector, and x-axis being the energy of those photons. Now, we are supposed to integrate over the spike with different methods (both numerically and analytically, as we have) but we both just fail to understand what it is that we get from integrating it!

The incoming photons are coming from an Am-241 sample being 59.6keV and our spikes are slightly lower (~50keV) just like they should be. As an example integrating our first sample: The spike was at 51.5keV and integrating over it in matlab (after finding a proper distribution function for it) gives us 68.74keV.

What is it that this 68.74keV integral is supposed to tell us here? It isn't the total energy of all the photons that hit the region since the number of photons that hit there was around 250 of them? The total energy over the whole measurement should be like ~12MeV. I don't see that working. We both just fail to see any logical way to interpret the result.

I'm guessing this is something really stupid that we just haven't been able to see or maybe we're just doing something wrong so I figured maybe the people here could offer their help. Thanks! :)

submitted by /u/vivals5
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How did Henry Cavendish manage to calculate the Earth's mass back in 1798?

Posted: 06 Dec 2016 03:03 PM PST

Is Radon Gas a real danger in homes?

Posted: 07 Dec 2016 12:14 AM PST

I am currently looking to find out whether Radon gas is actually a danger in some homes (specifically in Norway) or whether the dangers are greatly exaggerated.

I want to know because it will determine whether or not i can take a job as salesmen of devices that detect radon gas. I don't want to sell bullshit.

submitted by /u/langotriel
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How far away is the andromeda galaxy ?

Posted: 07 Dec 2016 03:27 AM PST

I wonder how far away the andromeda galaxy is. I know that it´s 2.5 million light years away...but it´s coming in our direction. So how far away is the galaxy right now ? I mean during these 2.5 million years the andromeda galaxy should be way closer than 2.5 million light years right now right ? Even tho we can´t see it yet. So if the actual distance is x light years it would need x years for us to see the andromeda galaxy as it is right now right ? So again how far away is the galaxy right now or how far away would we see the galaxy in 2.5 million years ?

submitted by /u/Shonity
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vào lúc No comments:

Tuesday, December 6, 2016

With many devices today using Lithium to power them, how much Li is left in the earth?

With many devices today using Lithium to power them, how much Li is left in the earth?

With many devices today using Lithium to power them, how much Li is left in the earth?

Posted: 05 Dec 2016 06:48 PM PST

What is the minimum amount of matter that may form a black hole?

Posted: 05 Dec 2016 09:32 AM PST

Measuring a star's wobble is used to detect exoplanets, but how can the technique differentiate between one, or greater than two objects?

Posted: 05 Dec 2016 12:52 PM PST

Thank you.

submitted by /u/GetInTheFight
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Could fusion power offset helium depletion?

Posted: 06 Dec 2016 05:33 AM PST

If we in an imagined future got say 10% of our energy from fusion. Would the helium biproducts be enough for to satisfy our need for helium in science? What about both science and "recreational" use of helium?

submitted by /u/tazfriend
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Whу іs саrtіlаgе sо slоw tо rераіr?

Posted: 05 Dec 2016 02:11 PM PST

Соuld іt bе duе tо сhоdnrосуtе рrоlfіеrаtіоn bеіng lоw, оr mаtrіх sуnthеsіs bеіng lоw, оr іs іt sоmеthіng еlsе whісh іs саusіng іt tо hеаl sо slоwlу?

submitted by /u/redditsci
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Why does water boil in a vacuum?

Posted: 06 Dec 2016 07:19 AM PST

My father told me that when he was a kid, he did a physics-experiment in his school where he put a glas of water in some sort of vacuumchamber. And as the chamber created a greater vacuum the water would more easily boil. I asked him why that is but he does not remember and he didn't pay that much attention anyway. How come water boils in a vacuum and does it boil no mather the temperture?

submitted by /u/TiruM8
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Can "quantum weirdness" be understood in terms of information?

Posted: 06 Dec 2016 04:30 AM PST

As far as I've been able to tell, in the quantum view, measurable physical entities are considered to be in two kinds of states: measured and non-measured.

When they are measured, the values of certain measurable values are leaked into another system (the measurement apparatus is one of these), and they get assigned a definite value.

So "measurement" simply means that information gets leaked from the measured system to the one that does the measuring.

Does it make sense to see measurement this way?

I've gathered this from reading about non-interacting measurement, that is, when the apparatus does not actually interact with what's measured, it just constrains its path in such a way so as to "know" what it's doing, even if it isn't actively checking. But when the experiment is set up in such a way so as not to leak information, physical systems evolve as if the measureable variables have all the possible values allowed by the experimental setup. This is usually called a "superposition".

Does it make sense to see superposition this way?

This seems to be the logic behind quantum computing: get some bits ready, isolate them informationally from the environment and let them go wild. Unmeasured, they will follow all allowed paths and compute things faster as if they were observed to follow specific paths. More types of logical gates are possible with new paths. You perform a measurement at the end to get the result.

Does it make sense to see quantum computing this way?

Entanglement seems to simply mean that two (or more) particles are informationally isolated from the environment, but not from eachother, with their measurable values correlated in a specific way. So they exist in their own "informational bubble", even when separated by large physical distances. A measurement of any of the entangled particles is like a breach in this bubble, which instantly reveals its entire structure to the system which measured it.

How's my take on entanglement?

From the point of view of any physical system, the evolution of other physical systems (including physical systems with only one member, single entities) is inevitably described by probability waves because as long as they are "out of touch", you can only have a vague hunch about what values they will have the next time you "connect" to them via measurement.

Does it make sense to view things this way? I work as a coder so thinking in terms of information transfer comes more naturally.

submitted by /u/Bubba_the_King
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How many stars were needed to supply all the elements in the solar system ?

Posted: 05 Dec 2016 06:29 PM PST

Hey there, first of all I know that there was hydrogen and some helium, lithium and berylium formed during the big bang. But the other day I was looking at a spoon and was just thinking "wow, this was forged inside a/some stars".

So, was our solar system seeded by a unique star, a few stars or a shitload of stars ? Is there anyway to know with isotopes ?

Thank you

submitted by /u/TheTurp
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How will fusion reactors harness energy?

Posted: 06 Dec 2016 07:06 AM PST

Over the years I have seen a lot about fusion reactors containing heat and energy. I understand the basic idea of containing plasma in a strong magnetic field. This way no energy gets transferred to the container. But I have never heard of a mechanism to safely use that heat/energy. How would one get the energy they are producing in a fusion reactor? I know how current fission reactors do it, but that system doesn't seem like it would work. Am I wrong?

submitted by /u/WimyWamWamWozl
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[Biology] Is there any advantage to having a slitted pupil over a round pupil?

Posted: 05 Dec 2016 03:17 PM PST

With LED lighting seemingly taking over the lighting market, how much phosphorous is left in the earth to be mined?

Posted: 06 Dec 2016 03:49 AM PST

Could a stationary bike with a generator really be used to power lights and simple appliances for 24 hours with only one hour of pedaling?

Posted: 06 Dec 2016 05:56 AM PST

http://news.nationalgeographic.com/energy/2015/10/151006-energy-drink-billionaire-wants-to-power-homes-with-bikes/

According to Manoj Bhargava (U.S. Billionaire 5 hour energy drink) he has built a stationary bike with a generator that can do just that. I remember going to the science centre when I was younger and pedalling my butt off on a stationary bike just to get a lightbulb to stay dimly lit. How efficient would the generator have to be to achieve 24 hours of power with only one hour of pedalling?

submitted by /u/hunter116
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Why is 683lm/W maximum efficiency?

Posted: 05 Dec 2016 11:55 PM PST

Currently studying for exams, and mye lecture book mentions that 683lm/W is max (theoretical) efficiency we can get out of a laser/anything that produces light?

submitted by /u/Clipperduck
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[Physics] Why does Nuclear Fusion only occur at such high heat?

Posted: 06 Dec 2016 07:10 AM PST

I'm curious as to why nuclear fusion must happen at such high heat (100 million degrees C) rather than being achievable at a lower temperature.

submitted by /u/idiotsonfire
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What scale does gravity start working on?

Posted: 05 Dec 2016 10:29 PM PST

I've heard before that gravity doesn't work on a quantum scale, so I assume this means that gravity doesn't effect quantum particles. However, where does it start working? Quarks? Sub-Atomic Particles? Atoms? Molecules? Do we even know?

submitted by /u/ohdaviing
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Is light outside the visible spectrum made out of photons? If so, how do they manage to penetrate walls unlike visible light?

Posted: 06 Dec 2016 01:35 AM PST

How did old satellites transmit photo's to earth? Did they have a digital camera?

Posted: 05 Dec 2016 10:32 AM PST

So how did they do it? Did they use CRT camera's and send an analogue video feed to earth? Of did they actually take photographs?

submitted by /u/domlang
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Is a perfect sphere of glass indestructible?

Posted: 06 Dec 2016 01:04 AM PST

I had a thought, where if there is a sphere of glass that is mathematically perfect, down to a subatomic level, would that sphere then be indestructible? My reasoning (which might be incorrect) is that Rupert's Drop (the glass droplets that are super strong) are so strong because there is the same amount of force being applied across the entire surface of the drop (minus the tail), and so if they are super strong even while having the miniscule imperfections, would a flawless one not be ultra strong or indestructible? Obviously this idea isn't physically possible but I'm just wondering from a mathematical perspective.

submitted by /u/electrcboogaloo
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With SSD speeds getting faster and faster, will they eventually supersede the need for RAM?

Posted: 06 Dec 2016 04:12 AM PST

how rare is a tectonic plate system in the solar system/known planets?

Posted: 06 Dec 2016 12:07 AM PST

How did the photon temperature drop in a matter dominated universe, while still coupled?

Posted: 05 Dec 2016 11:37 AM PST

For a pure radiation dominated universe the temperature (T) drops inversly to its scale factor (a), that is: T~a-1. For a pure matter dominated universe we have T~a-2. I would assume that in a matter dominated universe between 47000 years (radiation-matter equivalence) and 380000 years (photon-decoupling) after the big bang, the temperature of the universe would drop somewhere in between. However I have also read (in a random slide show pdf) that the photon temperature goes as T~a-1 in both cases. Which is true?

submitted by /u/Lassetass
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Why don't IR thermometers work well on shiny surfaces?

Posted: 06 Dec 2016 03:33 AM PST

If sound generates heat, how much or how loud of a sound would you need to get a 1°C increase in temperature?

Posted: 05 Dec 2016 05:04 PM PST

Theoretically

submitted by /u/Sgt_Wafflezz
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What caused the switch in the 40s from more girls to more boys to be born?

Posted: 06 Dec 2016 01:30 AM PST

So incidentally, while trying to learn python, I made an interesting discovery. I tried to do some excercises in data analysis and for that purpose downloaded the full register of US babynames from SSA available at their website. I managed to produce this curious graph.

As one can see there were more births of girls until the 40s, then the boys started to take over. In general I have heard that due to the fact that male sperm carries a Y chromosome which is lighter thatn an X-chromosome makes male sperm more likely to reach the egg first so we should expect more males to be born in general. However I don#t think biology was different before the 40s so I rather assume this is due to more complex reasons such as economic etc.

Thanks to anyone who can enlighten me!

submitted by /u/schawsk
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