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Thursday, December 14, 2017

Does a burnt piece of toast have the same number of calories as a regular piece of toast?

Does a burnt piece of toast have the same number of calories as a regular piece of toast?

Does a burnt piece of toast have the same number of calories as a regular piece of toast?

Posted: 13 Dec 2017 09:48 PM PST

What causes mental fatigue and how does it compare to muscular fatigue?

Posted: 13 Dec 2017 09:11 PM PST

How do we know that gravity has infinite range?

Posted: 13 Dec 2017 09:16 PM PST

can someone who suffers from Alzheimer dream?

Posted: 14 Dec 2017 03:51 AM PST

What is the Correlation length of Temperature?

Posted: 14 Dec 2017 05:55 AM PST

Cities that are close to one-another will have temperatures that are correlated; a hot day in one will likely be a hot day in the other. Cities that are farther apart will generally have uncorrelated temperature, except due to global fluctuations (December is colder than July in both New York and LA). So, what is the typical correlation distance of temperature?

Just playing around with Wolfram Alpha, Chicago and New York look uncorrelated, New York and Boston are totally correlated, whereas New York and Detroit are weakly correlated. So, I estimate the correlation length at about 1000 km, but I imagine it's different EW vs NS.

submitted by /u/iorgfeflkd
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Why is going on your tip-toes easy, when doing a push-up is difficult?

Posted: 13 Dec 2017 08:35 PM PST

I was just sitting in a position like this and was slowly raising and lowering myself on my toes as a sort of stretch. After a little bit, I began kind of freaking myself out, because it feels like I'm lifting my entire bodyweight using only my toes.

Why is this so simple to accomplish, when a different way of moving your body up and down (a push-up) is relatively difficult?

DISCLAIMER: I feel like this is a very dumb question. I wish I could say that I'm drunk or something, but no, I'm just in my room raising and lowering myself on my toes.

submitted by /u/justlikejohnnymarr
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Is there a sequence of moves that can be applied to a Rubik's Cube that results in iterating the cube through every possible state exactly once?

Posted: 13 Dec 2017 11:00 PM PST

Have any animals developed projectiles?

Posted: 13 Dec 2017 06:24 PM PST

Whether through technology or through bodily functions.

submitted by /u/quackbass
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Did the construction of the LIGO gravitational wave detector account for the curve of the earth? Did each end of have to be risen up a bit so that each light beam was perfectly straight?

Posted: 14 Dec 2017 12:07 AM PST

How can a supernova get brighter, even after it's "peak brightness"?

Posted: 14 Dec 2017 03:47 AM PST

I found a graph comparing the brightness of different kinds of supernova brightness'. The link is from another post in this subreddit and i don't claim any rights to it. I was just interested in how thy behave. Sorry for poor english.

From here: https://physics.stackexchange.com/questions/61872/how-long-does-a-supernova-last

submitted by /u/Numree
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How much electricity can travel on a transmission line?

Posted: 13 Dec 2017 09:26 PM PST

I'm trying to understand electricity transmission using an analogy of distribution of water. In this case the transmission lines are the pipes, but what would their capacity be? If I say the lines are 138kV for example does thst give me any idea of how 'big' the pipe is, and therefore how much electricity I can transmit per unit time?

Thank you!

submitted by /u/monkeyjazz
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What is information and why is it lost in a black hole?

Posted: 13 Dec 2017 11:51 AM PST

Do other mammal species, like pigs, have an Adam's apple?

Posted: 13 Dec 2017 07:33 PM PST

How do we know black holes can die if we have yet to see it happen?

Posted: 13 Dec 2017 04:40 PM PST

I've been searching for a minute and I can find plenty of information suggesting that black holes will eventually evaporate, I can't find any info on when or where the evidence we have for it is other than extrapolated equations.

I'm mostly just unsettled by the fact that I can't seem to find any evidence of black holes completely evaporating and I get worried about our universe.

submitted by /u/Servicemaster
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Is there any way to, overnight, neutralize or otherwise nullify the danger of the Elephant's Foot in Chernobyl?

Posted: 13 Dec 2017 09:33 AM PST

the -admittedly brief- wiki page states that Chernobyl's Elephant's Foot "will remain radioactive for over 100,000 years".

if cost and resource availability were not an issue, would there be any way to neutralize such an intensely dense and radioactive site/object overnight (or in a reasonably brief amount of time)?

side question: what is currently being done about it, and in what ways are scientists trying to make future progress in dealing with it?

submitted by /u/BartlettMagic
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If a nuke explodes mid-air, does the mushroom cloud still form?

Posted: 14 Dec 2017 01:46 AM PST

Is it possible to refine iron ore in a vacuum?

Posted: 13 Dec 2017 09:12 PM PST

Why do the bottoms of glass beer bottles pop off when tapped?

Posted: 14 Dec 2017 12:57 AM PST

I just saw this post https://www.reddit.com/r/instant_regret/comments/7jmhe4/there_is_always_that_unlucky_friend/ and I see that the top comment explains it as heating but I don't think that's it, looking at the delay, the heating may have made it weaker but I think it's the same effect. I have seen people do this with soda bottles before.

For that matter I remember that post where the guy talks about what happens if a glass was actually half vaccum at the bottom and half water at the top. Is this similar in anyway?

submitted by /u/Anantgaur
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Where are quantum behaviours/phenomena (coherence, entanglement, etc...) actually occurring outside of controlled laboratory conditions?

Posted: 13 Dec 2017 11:52 AM PST

Given the general "noisiness" of everything happening within our own bodies, across the surface and within the atmosphere of the planet, and the relative "warmess" and "non-emptiness" of even interstellar space (bottoming out somewhere around 2.7 Kelvin and home to oodles of molecular hydrogen?), are the overwhelming majority of fundamental particles which compose matter always in a state of decoherence, and as such never exhibiting any quantum behaviour?

I imagine that light, given that it obeys Bose-Einstein statistics is often exhibiting quantum behaviour during travel, but I really have no idea.

Basically I'm wondering where and to what extent are quantum behaviours occurring "naturally" (ie. outside of controlled laboratory conditions).

I'm just a layman with an interest, so I apologize if this question doesn't make too much sense, I'll try and elaborate if necessary.

submitted by /u/50millionfeetofearth
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Wednesday, December 13, 2017

How were roots and logarithms inititially calculated without the use of calculators?

How were roots and logarithms inititially calculated without the use of calculators?

How were roots and logarithms inititially calculated without the use of calculators?

Posted: 12 Dec 2017 09:51 PM PST

Right now all I do is use the root, log or ln button in my calculator and it spits the answer out. Is there a systematical way of calculating this by hand?

submitted by /u/Magisidae
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How long does a supernova last?

Posted: 13 Dec 2017 04:33 AM PST

If a star exploded near enough to Earth for us to be able to see it, how much time would we have to enjoy the view before the night sky went back to normal?

submitted by /u/VelvetPoltergeist
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What selection pressures caused gender/sex to evolve?

Posted: 13 Dec 2017 02:19 AM PST

Since life came from a single celled organsim, what are the selection pressures that could've caused mutations/genes that resulted in genders?

Bonus questions I'd much appreciate if you could answer:

  • What selection pressures along with changes in genes caused different developments of sexual reproduction mechanisms? In essence how is it that some species reproduce in a manner that is completely different from a species whom not long ago came from the same ancestor?

  • Are their species where more than two genders/sexes evolved?

Thanks in advance.

submitted by /u/962rep
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Why isn't the atmosphere of Jupiter homogeneous?

Posted: 12 Dec 2017 06:24 PM PST

After what I would assume is a few billion years of mixing, why are there still such defined patterns in Jupiter's atmosphere? Why are the layers not homogeneous? Does it have to do with updrafts mixing more dense layers?

submitted by /u/Now_Plain_Zero
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What do the dot product/the tensor product of two vectors represent geometrically?

Posted: 12 Dec 2017 07:50 PM PST

So the cross product isn't too hard to understand conceptually, since there's an actual geometric representation for what it is (if a x b = c, then c is perpendicular to a and b and has a magnitude equal to the area of the parallelogram made by a and b (E: that goes in the direction according to the right-hand rule)). But what about the dot/tensor product? I know how to do them, but what exactly do they represent geometrically?

submitted by /u/Popopopper123
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How do ISP's limit the speeds I get?

Posted: 12 Dec 2017 05:27 PM PST

Is there any element that can form 8 or more covalent bonds?

Posted: 13 Dec 2017 05:49 AM PST

Or is the maximum permissible bonds seven like in IF7?

submitted by /u/DeltaEmerald11
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Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science

Posted: 13 Dec 2017 07:07 AM PST

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Physics, Astronomy, Earth and Planetary Science

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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Does the gritting/salting of our roads during winter have any significant impact to the salination of the waterboard?

Posted: 13 Dec 2017 02:45 AM PST

What is our best information about the origin point of intersteller asteroid Oumuamua?

Posted: 12 Dec 2017 10:20 AM PST

The first information I cam across (more than one science journalism source) suggested the star Vega, in Lyra. This seems pretty specific. Another source suggested that this thing had been travelling for so many billions of years that if it came from the area of sky that is now occupied by Vega, Vega wouldn't have been there at the time.

More recent updates have suggested the southern constellations of Carina and Columba. I don't have any astronomy-related training at all, but isn't that that a completely different chunk of sky?

...new here; hope I followed all the correct formats.

submitted by /u/tygrebryte
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Whats the difference between liquid and gas?

Posted: 12 Dec 2017 11:34 AM PST

I know this many sound like an extremely simple question, but on a molecular level, what's the difference between a liquid and a gas? From a young age we're shown a collection of diagrams showing how the structure of molecules in solids, liquids and gases differ. In diagram of the solid, they're touching, in the liquid, they're spaced apart and less structured, and in the gas, they're even further apart. My assumption has always been (feel free to correct me if I'm wrong), that difference between a solid and a liquid is the molecules 'touching', there molecular bonds. When a substance becomes hot enough that's its molecules have enough energy to break there bonds, it becomes a liquid. We have a definite point in which a solid becomes a liquid. Equally, there is a definite point when a gas becomes a plasma, when the molecules gain enough energy that there atomic bonds begin breaking down, making a soup of protons electrons and the works. ...but what's the definite point between liquid and gas? Are there any properties that a gas has the a liquid does not? Theoretically, if we had a liquid and a gas of the same density, how would they behave differently? Maybe a slept though a key part of my year 6 science classes and missed something. Help me atone for my younger laziness reddit!

submitted by /u/Flyingnutkick
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How can you make antimatter in a particle collider?

Posted: 13 Dec 2017 01:23 AM PST

I understand that you can find new sub particles by hitting two hadron together in near light speed such as higgs boson. But how can you reverse the electric charge of an atom in that way?

submitted by /u/Numree
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Do we all see the same color when looking at the same thing?

Posted: 12 Dec 2017 02:02 PM PST

We all know the grass is green, but could someone's "green" be someone else's red or blue? Do other people see things in various different colors but associate that color by the same name we've always known it as?

submitted by /u/LightWithoutLaz
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If axial tilt causes the seasons at temperate latitudes, then why don't the poles experience extremely hot summers when the sun is out all day, and even *more* extreme winters when the sun remains set all day?

Posted: 12 Dec 2017 03:05 PM PST

Are earthquakes worse if you are many stories above? Or if you are many floors underground?

Posted: 12 Dec 2017 06:56 AM PST

Is it possible to use The Hubble Telescope to look at the interstellar asteroid in our solar system?

Posted: 12 Dec 2017 10:36 AM PST

I've seen that SETI want to use radio telescopes to listen to the first interstellar object in our solar system (that we know of), would it be possible to use the Hubble Space Telescope to get a better look of it?

submitted by /u/Killco_Joe
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Does temperature have an effect on cables like HDMI or ethernet? If so, how?

Posted: 12 Dec 2017 07:05 AM PST

For example: say you routed an ethernet cable from a computer to a modem. The cable lays above a heater which then another section of the same cable lays in front of, say, a door to the outside which cold can come through. Then the rest of the cable goes into a computer.

Would the cold and heat do anything to the connection or the cable itself in general?

submitted by /u/PM_For_Help
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Have the Hawaiian islands gotten bigger or smaller over time?

Posted: 12 Dec 2017 01:57 PM PST

Have they gotten smaller because of global warming? Were they larger or more prominent 150 years ago before industrialization? Is it possible their size would change regardless given their geographical location? Are they going to disappear and what may cause that?

submitted by /u/emsiii
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Are there any "rock-paper-scissors"-genes?

Posted: 12 Dec 2017 06:12 AM PST

I'm in my last year of high school, and learning about genetics. So far, we've covered dominant and recessive genes, as well as codominance and such. Are there any genes where the alleles dominate each other like in a game of rock-paper-scissors?

submitted by /u/Mirriet
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How does the geographical spread of influenza work?

Posted: 12 Dec 2017 01:22 PM PST

I've always thought of influenza as a cold weather illness, which by and large, it seems to be. Australia was hit particularly hard this winter, and now that the seasons are changing, they're seeing a slowdown.

Now, the northern hemisphere is starting to get sick, and I was looking at the map of the US on the newest CDC report. I've always known it tends to start in the southern US and work it's way up, but why is that? Do we know? Areas where it is truly the coldest right now have sporadic cases, but the deep south is already at high levels. If it is a cold-weather illness, why doesn't it start spreading the fastest in the areas that are the coldest, where people are shut in and spreading germs already?

submitted by /u/tinygiggs
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Tuesday, December 12, 2017

Is there a limit on how long a power cord can be?

Is there a limit on how long a power cord can be?

Is there a limit on how long a power cord can be?

Posted: 12 Dec 2017 01:44 AM PST

Probably a stupid question, but I was joking around about ice frozen on the moon, and how we can melt it by using a hair drier with a super long cord. This got me thinking though… if there was a cord that long, there'd be a huge delay as the electricty travels up the wire.

But then I thought even more… would the electricity even reach the hair drier? Is there a limit to how far electricity can travelalong a wire? I imagine some of the energy is lost when it has to travel. So, would a power cord to the moon even work?

submitted by /u/Vicorin
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I know it takes two weeks for the flu vaccine to be fully effective. I assume effectiveness is zero right before the vaccine is administered, and maximum after two weeks. But is there a graph that shows how effectiveness changes in time?

Posted: 11 Dec 2017 12:40 PM PST

Basically, I'm curious to know, for example, when is it 50% effective, or how soon does it get to 90%, etc.

I'm sure data exists that could allow plotting that graph - I just could not find it myself. Thanks!

submitted by /u/florinandrei
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Why the Antarctic ice cap stays in one place and does not drift freely like an iceberg?

Posted: 12 Dec 2017 12:35 AM PST

Also, what is the size of the largest iceberg that can break off and drift away? Like, can the massive ice cap break in half and one half escapes?

submitted by /u/promieniowanie
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Why is the separation constant for the radial equation of the Hydrogen atom in the form of L(L+1)?

Posted: 11 Dec 2017 02:46 PM PST

Hello everyone,

I know that solving the Schrodinger equation for the Hydrogen atom requires separation of variables. When doing this, why are the separation constants of a particular form? E.g. the separation constant for the radial equation is l(l+1), rather than just, say, l. What is the reason for this?

Thanks.

submitted by /u/DoctorKokktor
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Why can some viruses (smallpox, polio) be virtually eradicated while others cannot (HIV, influenza)?

Posted: 11 Dec 2017 08:57 PM PST

I have a few ideas, but would like to learn some more concrete and detailed reasons.

submitted by /u/pgreen08
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How does a coax splitter work?

Posted: 12 Dec 2017 02:43 AM PST

I've seen the inside of it and it looks like a bunch of resistors and capacitors between the input and output, so I'm assuming it's doing some noise filtering.

Why would you do this? Don't you want whatever's at the input to be exactly the output?

submitted by /u/yosimba2000
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Is there a link between a metal being conductive from an electric standpoint and it being magnetic? If so, what is the cause?

Posted: 12 Dec 2017 01:36 AM PST

For example, lead is a great conductor of electricity, but you can't stick a magnet to it. If electromagnetism is one unified aspect of physics, how is this reconciled with the differences between two seemingly separate aspects of physics? Or if I'm wording the question wrong, how should we separate aspects of electricity and magnetism?

submitted by /u/CraptainHammer
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If the capacity of a battery charging another battery drops below that of the receiving battery, will it stop transferring electricity since the electrons will no longer prefer to leave the lower energy "state" of the drained battery?

Posted: 11 Dec 2017 04:01 PM PST

Is the above reverse motion of electrons to the lower-capacity battery prevented by the orientation of + and - wires, or would the partitioned layout of the cathodes and anodes prevent it? I am assuming entropy would be the main motivation for electricity stopping its flow if the above is true.

submitted by /u/ssinatra3
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If our bodies are conductive, can holding a battery between two fingers deplete it completely?

Posted: 11 Dec 2017 06:25 PM PST

Let's say you have a new AAA battery and hold it between your thumb and index finger. Given that the human body has some resistance, but is still conductive, if you hold it for a long enough time, can you deplete it completely? How long would it take?

submitted by /u/silviakcamara
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What can stop and/or destroy a black hole?

Posted: 12 Dec 2017 12:59 AM PST

Can black holes be stopped somehow or they continue endlessly to absorve everything around them?

submitted by /u/AsymaCr
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How/why are so many mathematical proofs and theorems contingent on the Riemann hypothesis being true?

Posted: 11 Dec 2017 10:41 AM PST

How is it possible to prove anything using an unproven theorem? Is the converse also true (that is, if the Riemann hypothesis is false, are theories contingent on it also proven false?)

What type of theorems depend on the Riemann hypothesis? How is it useful to make such an assumption?

submitted by /u/piecat
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Are there any ant species that don’t live in colonies?

Posted: 11 Dec 2017 06:38 PM PST

Do they update the voyager software?

Posted: 11 Dec 2017 08:04 AM PST

I was watching a documentary on the voyager satellites yesterday and was wondering about the software on it.

Has the software been unchanged since it launched? If you could send a signal to earth from that far away could you issue software updates as needed?

Also, what language was the software coded in?

Thanks reddit!

submitted by /u/The_Peter_Quill
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How did the Russian Woodpecker receiver work?

Posted: 11 Dec 2017 09:16 PM PST

So I (roughly) understand how the Russian Woodpecker's OTH radar worked. Bouncing radio waves over the horizon, interpreting the bounce back, and extrapolating moving objects therein. But I've always wondered about the enormous array at Chernobyl, which I only found out today was just the receiver, with the transmitter about 50km away. How did the enormous receiver work to catch signals? Why all the crazy trapezoids/funky shapes? What actually 'caught' the signal and what was just support? If this was an effective design, why don't we see it elsewhere?

submitted by /u/polishprocessors
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What is meant by the heat death of the universe?

Posted: 11 Dec 2017 06:55 PM PST

Does it mean something like all matter will cease to exist or will it return to a state similar to "time" (even though time technically doesn't start before the big bang if I am not mistaken) before the big bang? Or are these ideas completely off?

From a basic google search, it says that it is a state where entropy cannot increase and thermodynamic processes can no longer occur. What does this mean for the matter of the universe?

submitted by /u/Haz_Matt
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Does language affect learning and studying?

Posted: 11 Dec 2017 06:12 AM PST

What I mean by this is do different languages explain concepts better and can you learn something better in another language. Say person A is equally fluent in 2 languages and the person is studying something which has specific terms and concepts. Is it better to study with one language than the other. Could it be different when studying in different ways(viewing, listening).

submitted by /u/Santru10
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If the strength of an acid is based on concentration, why are acids like Sulfuric Acid always considered so dangerous compared to others?

Posted: 11 Dec 2017 06:40 PM PST

I was in a lap and we were working with acetic acid (vinegar) and it was highly concentrated. This idiot says something along the lines of Vinegar aint dangerous and takes a sip. I then watched him spit out his gums.

Why is it that acids like Sulfuric, Nitic, etc are always portrayed as these ultimately corrosive substances despite concentration? Is there something to these "famous" acids that make them more deadly?

And arent bases scarier to spill on you?

submitted by /u/Neato_Orpheus
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From what I have learnt so far, refrigerators use chlorofluorocarbons for cooling. Do these chlorofluorocarbons run out after some time? If yes how are they replenished?

Posted: 11 Dec 2017 07:29 AM PST

Microwave Ovens and Wi-Fi Signals Operate at The Same Frequency (2.4GHz). What Makes Microwave Ovens More Dangerous?

Posted: 11 Dec 2017 08:39 PM PST

A small amount of Googling tells me it has to do with the power supplied. What I'm looking for is an easy and succinct explanation to convince a friend, who says wi-fi is just as dangerous because they have the same frequency, that there is a difference. I can't get through to him and may be a lost cause, but I'm not great with words in the heat of the moment so feel like I'm failing him, when I should have an answer.

submitted by /u/BumblingCumbersnatch
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