Pages

Wednesday, March 27, 2019

Do people who were sleep deprived during adolescence tend to crave sleep as adults more often than their body really needs?

Do people who were sleep deprived during adolescence tend to crave sleep as adults more often than their body really needs?


Do people who were sleep deprived during adolescence tend to crave sleep as adults more often than their body really needs?

Posted: 26 Mar 2019 05:35 PM PDT

I'm thinking in terms of people who grew up with not a lot of food. As adults when they eat they might tend to scarf it down or hoard it for later. Even though they have plenty to eat now, they are still psychologically effected from not having much when they were growing up. Would behaviorisms like that occur from sleep deprivation?

submitted by /u/Ceauxgan
[link] [comments]

The Tsar Bomba had a yield of 50 megatons. According to Wikipedia "the bomb would have had a yield in excess of 100 megatons if it had included a uranium-238 tamper". Why does a U-238 tamper increase the yield as opposed to other materials or no tamper at all?

Posted: 27 Mar 2019 05:03 AM PDT

I have a very bare-bones understanding of how nuclear weapons work.

submitted by /u/Pukalo_Reincarnate
[link] [comments]

At which size do particles start casting shadows instead of behaving according to the Fraunhofer diffraction?

Posted: 27 Mar 2019 02:09 AM PDT

We just learnt about Rayleigh, Mie and Fraunhofer and neither our Prof nor his contacts could sufficiently answer at which particle size the particle becomes too large for Fraunhofer diffraction and instead casts a shadow, like a regular ball for example.

submitted by /u/Crotaro
[link] [comments]

Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology

Posted: 27 Mar 2019 08:12 AM PDT

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
[link] [comments]

What is the explosion speed of gasoline?

Posted: 27 Mar 2019 07:12 AM PDT

I was looking this up because I was wondering how fast someone would have to run to out run a gas fireball. But I couldn't find it anywhere.

submitted by /u/Syndr1l
[link] [comments]

How does blending fruit/veg change nutrient content and uptake by the body?

Posted: 27 Mar 2019 12:50 AM PDT

I have read that blending can change the speed with which your body absorbs sugars, making blood sugar spike rather than slowly releasing sugar (when you eat the food). But does blending change the vitamin or micronutrient contents of the food? E.g. a smoothie of spinach, blueberries, strawberries, apple juice.

submitted by /u/Stru-bear
[link] [comments]

Do animals experience the same side effects of "neutering" that humans do?

Posted: 26 Mar 2019 04:13 PM PDT

If a human gets his/her testes/ovaries removed, they go through a host of symptoms. Hot flashes, dry skin, vaginal dryness, tiredness, decreased muscle mass, etc, due to the lack of hormone generation. Do animals, have similar symptoms when they get neutered? (By the way I'm mainly talking about cats and dogs in comparison to humans, but I'm open to other comparisons too.)

Neutering also doesn't seem to have any negative affect on the appearance of an animal (Like menopause in women). And it has a positive affect on their temperament. Neutering seems to have net positive consequences for animals, but more mixed results for humans. Is this correct or am I missing some information?

A positive side effect neutered humans and animals share though, is increased longevity.

submitted by /u/StrangeApeCreature
[link] [comments]

What makes hard material (glass for exemple) shatter when broken compared to softer materials just distorting?

Posted: 27 Mar 2019 04:13 AM PDT

Is there a Y shaped magnet? If yes then what are its poles like?

Posted: 27 Mar 2019 12:05 AM PDT

How do Robin's, or any other bird, find worms in the soil? Do they use sight?

Posted: 26 Mar 2019 03:05 PM PDT

I live in Wisconsin in a quiet neighborhood so I have a lot of different birds in my yard most of the year. I know I could ask Google, but Reddit is way more informational, and way more hilarious. Thank you.

submitted by /u/bells_on_your_face
[link] [comments]

A lot of medicine dosages are based on weight, does it matter if the weight is made up of muscle or fat?

Posted: 27 Mar 2019 03:21 AM PDT

For example, would a 10% bodyfat 120kg male bodybuilder require the same dose as a 50% bodyfat 120kg sedentary man?

submitted by /u/andreasdagen
[link] [comments]

How does loaf balancing of electric grid work?

Posted: 27 Mar 2019 02:58 AM PDT

As I understand, the electric grid needs to have exactly the amount of electricity necessary to accommodate a given number of users. How can an electric grid adjust its power every time a user is connected/disconnected? This adjustment seems to be needed instantaneously, but I suppose it takes some time to increase or reduce the power.

submitted by /u/ted_kingdom
[link] [comments]

How do viruses that code for lysozymes not end up lysing their host cell too soon?

Posted: 26 Mar 2019 12:36 PM PDT

My biology teacher wasn't able to answer this question so I turned to you guys. If a virus is non-enveloped I was told that they would escape their host cell during the final step of the lytic cycle. Lysozymes would Lyse the host and all the virions inside would escape to infect more cells. My question was, if the lysozymes were coded for in the virions' nucleic acid, wouldn't they be produced at the same time as the other viral components? And if this was the case wouldn't the virus shoot itself in the foot so to speak by lysing it's host before enough virions were produced? Thanks in advance for reading and I hope somebody can shed some light on this topic for me.

submitted by /u/the_muffin
[link] [comments]

How far down the eukaryote tree into unikonts towards animalia do we find fruiting bodies as a form of reproduction?

Posted: 26 Mar 2019 05:54 PM PDT

People like to mention that mushrooms are closer related to animals than to plants.
While pondering thing, I noted that fruiting is something that both plants and fungi use for propagation.

I can't think of a quick or easy way to look this up (having to go into each kingdom, etc.) so was hoping someone here happened to know. So what's the closest organism to an animal that still fruits?

submitted by /u/meoka2368
[link] [comments]

What's happening inside the computer when it "hangs" and won't respond?

Posted: 26 Mar 2019 02:08 PM PDT

I have this old laptop that I've been trying to coax into doing basic tasks but it seems to have trouble even maximizing a window without stopping to think about it for a good 30 seconds. So what's going on inside the computer when it freezes up trying to do a simple task? Why does it freeze up in the first place?

submitted by /u/raviolibassist
[link] [comments]

Where Does The Space From Deleting Files Come From?

Posted: 26 Mar 2019 05:53 PM PDT

When I delete/uninstall a file (say, a 30 GB video game), I get an extra 30 GB on my PC.

BUT, aren't the files just sent to the Recycle Bin? I can retrieve and reinstall them whenever I want to, so they're obviously still stored on my PC.

Where does this extra space come from?

submitted by /u/Shrish3001
[link] [comments]

Aside from aluminum, what percent of American single stream recycling actually gets recycled on average?

Posted: 26 Mar 2019 11:59 AM PDT

I know we're no longer exporting recyclable waste to the extent we used to: https://www.nytimes.com/2018/05/29/climate/recycling-landfills-plastic-papers.html

I also imagine there's a huge variation between the contents of people's single stream recycling (oil coated pizza boxes going in recycling at one person's house, but the trash at another's) from household to household. We used to add glass to our recycling bins, but were told to stop and then agreed to a $5 surcharge for a separate glass only basket that we can use to recycle just glass.

I loved (I know this is weird) the painful calendar and trash room my Japanese condominium had where I could recycle batteries separate from clear glass separate from colored glass separate from cardboard, etc., etc. In the interest of actually recycling in a meaningful way, I'd rather dial back what I throw in my recycling bin than err on the side of throwing in a bunch of stuff that may make recycling it less practical.

Anyone have any good, clear, recent info on this they can share? It's something I'd like to better understand.

submitted by /u/jxnfpm
[link] [comments]

What determines how large (or small) the flame on the wick of a lit candle becomes?

Posted: 26 Mar 2019 09:46 PM PDT

While watching a new candle burn on a desk across from me, I noticed that its flame reaches higher than the previous candle I had. I thought it might be the length of the exposed wick, but that's about the same as the other one.

I'm also thinking about how bunsen burners have higher flames when you burn more gas, but I'm not quite sure how that connects here (if at all) since flame height was still different even when the candles were brand new.

submitted by /u/nekothotsume
[link] [comments]

Can exist a 0-dimension manifold?

Posted: 26 Mar 2019 04:45 PM PDT

I start with an example:

SL(1,R) (it should be valid also in C and in H) in theory is a 0-dimension manifold (it is a manifold with dimension 12 - 1 = 0) (SL(1,R) are the matrix with determinant equal to 1, if it is 1x1 then is the only number 1)

The problem is, can a manifold have dimension equal to zero? (Can a Manifold being a point?)

Or the dimension should be at least one?

submitted by /u/Axel112358
[link] [comments]

Why do helicopters lose the max amount of lifting weight at higher altitudes? *SPOILERS FOR MOVIE TRIPLE FRONTIER*

Posted: 27 Mar 2019 01:05 AM PDT

I recently watched Triple Frontier and in it they need to lift 6000 pounds above the andes mountains. The helicopter they use was told to be able to lift 9000 under 2000 ft. They ended up going past the 2000 limit while flying and the helicopter ended up crashing. Is this just hollywood or do helicopters lose the amount of weight they can carry the higher they go? And if so why? (Sorry if flair is wrong I don't know if this would be engineering or physics)

submitted by /u/ImXTooNinjaxX
[link] [comments]

How does X-ray crystallography work?

Posted: 26 Mar 2019 07:01 PM PDT

Tuesday, March 26, 2019

When did people realize that a whip crack was breaking the sound barrier? What did people think was causing that sound before then?

When did people realize that a whip crack was breaking the sound barrier? What did people think was causing that sound before then?


When did people realize that a whip crack was breaking the sound barrier? What did people think was causing that sound before then?

Posted: 26 Mar 2019 02:07 AM PDT

Does an octopus have a dominant tentacle?

Posted: 25 Mar 2019 02:52 PM PDT

Do we permanently blind deep sea creatures when we point spotlights at them in their natural habitat?

Posted: 25 Mar 2019 03:46 PM PDT

Basically as above. Got me thinking whilst watching Blue Planet. Some creatures appear not to have 'eyes' (at least in the classical sense), so perhaps they use other senses for survival, navigation, etc, and therefore aren't affected. On the other hand, surely shining a light from an ROV or manned submersible, even of low luminosity/brightness/whatever, at creatures who possess some kind of vision would immediately blind them and thus reduce their chances of survival to zero?

submitted by /u/-drmw-
[link] [comments]

If I stick my head out of a car window at 65 mph and try to look directly ahead I’m effectively blinded by the air rushing passed my eyes. How does a cheetah see and track prey when running at top speed?

Posted: 26 Mar 2019 07:33 AM PDT

What was the Amazon like when the Sahara was green?

Posted: 25 Mar 2019 02:31 PM PDT

So the Amazon gets a lot of its nutrients from Saharan dust. I recall, however, that the Sahara undergoes periodic greening periods due to climatic changes, when dust would presumably be prevented from being kicked up by vegetation and relatively damp conditions. What happens to the Amazon during these periods?

submitted by /u/InterplanetaryCyborg
[link] [comments]

How do computers allocate resources?

Posted: 26 Mar 2019 02:08 AM PDT

If a computer is doing something in the background, say rendering video, and something in the foreground, say browsing the web, and the web browsing is lagging, why doesn't it automatically redirect resources to ensure that the foreground task is smooth, and devote only the excess resources to the background task?

Or does it?

How do computers allocate resources?

submitted by /u/benjaminikuta
[link] [comments]

In the event of an heart attack why is it an either or decision between thrombolysis and angioplasty? Why can't both be done at the same time or successively?

Posted: 26 Mar 2019 04:07 AM PDT

Non-native English speaker here.

From what I understand, in the event of an ongoing heart attack the doctors must choose between thrombolysis or an angioplasty with stenting/PCI (PCI and Angioplasty are the same thing right?). But both cannot be done.

So suppose someone is very far away from a hospital with angioplasty facilities. Why can't they be given thrombolysis first to save heart muscle and then when they reach the hospital after an hour they are treated with angioplasty with stents? Why does it have to be an either or decision?

submitted by /u/Experimentalphone
[link] [comments]

When you recieve a blood donation, what happens to the DNA of the blood you recieved?

Posted: 25 Mar 2019 01:41 PM PDT

Why do Tetanus shots hurt more than flu shots?

Posted: 26 Mar 2019 07:31 AM PDT

I get flu shots every year and seldom feel the shot as more than just a small jab and never feel any discomfort at the injection site afterward.

I got a Tetanus (DTAP) shot yesterday and holy fuck does my arm hurt! The shot hurt going in and my deltoid hurts today.

They appeared to be the same volume of "stuff" so I can't chalk it up to a larger injection volume.

Any ideas?

submitted by /u/sjvmi87
[link] [comments]

If I have two devices (a remote and a flashlight, or whatever) each using two common AA/AAA/D batteries, but only one of them has 100% remaining useful battery power and the other one has 0%... Can I theoretically swap one battery in each device and increase the power of each device to 50% life?

Posted: 25 Mar 2019 03:59 PM PDT

How do people who study fluid mechanics get accurate positional data on things like air and water?

Posted: 25 Mar 2019 03:21 PM PDT

I know there are things like pressure and motion sensors exist but I don't understand how someone might track the general flow of water in a tank.

submitted by /u/EudaiGG
[link] [comments]

On a calculator, Square root of -1 gives you a math error, but -1 to the power of 1/2 gives you -1. Why is that?

Posted: 25 Mar 2019 07:19 PM PDT

Root of 9 is 3, 9 to the power of 1/2 is 3. Root of 1 is 1, 1 to the power of 1/2 is 1. Root of -1 gives you an error, -1 to the power of 1/2 is -1.

How come?

submitted by /u/throwaway_8098
[link] [comments]

Why does your mouth water when you're about to throw up? Wouldnt the increased saliva make nausea worse?

Posted: 25 Mar 2019 12:40 PM PDT

Is all space expanding the same everywhere?

Posted: 25 Mar 2019 10:03 AM PDT

Is a cubic foot of interstellar space expanding the same as a cubic foot of intergalactic space?

submitted by /u/Dls95405
[link] [comments]

Is tree bark an ancestral trait in Gymnosperms and Angiosperms or did both species evolve it separately?

Posted: 25 Mar 2019 08:35 AM PDT

I'm more of a human anatomy and health sciences fella but this made me curious. In my biology class we're on plant physiology. Gymnosperms and angiosperms are both seed bearing plants and both contain species which have bark. All gymnosperms, to my limited knowledge, have bark while there are many angiosperm trees as well. However, many angiosperms don't have bark. Did angiosperms evolve away from bark and to a fleshier stalk?

submitted by /u/Lothken
[link] [comments]

why do hiccups occur?

Posted: 25 Mar 2019 03:11 PM PDT

Since there is a limited amount of energy in the Universe, isn't there a maximum max temperature?

Posted: 25 Mar 2019 11:05 AM PDT

Title.

submitted by /u/Dat_Peep
[link] [comments]

How did where the land meets the sea in Ireland result in cliffs and not beaches like everywhere else?

Posted: 25 Mar 2019 10:04 AM PDT

I know that through evolution one species can become another species, but at what point does one species turn into another?

Posted: 25 Mar 2019 12:20 PM PDT

I also don't know what flair to put, so I put chemistry

submitted by /u/The-Beat-is-Fope
[link] [comments]

Monday, March 25, 2019

What’s that lump in your throat you get when you’re about to cry?

What’s that lump in your throat you get when you’re about to cry?


What’s that lump in your throat you get when you’re about to cry?

Posted: 24 Mar 2019 12:02 PM PDT

Is there an example of a mathematical problem that is easy to understand, easy to believe in it's truth, yet impossible to prove through our current mathematical axioms?

Posted: 25 Mar 2019 05:56 AM PDT

I'm looking for a math problem (any field / branch) that any high school student would be able to conceptualize and that, if told it was true, could see clearly that it is -- yet it has not been able to be proven by our current mathematical knowledge?

submitted by /u/Stuck_In_the_Matrix
[link] [comments]

How do optometrists get prescription for babies?

Posted: 24 Mar 2019 12:00 PM PDT

Just saw the cutest post on r/wholesomegifs of a baby getting glasses and being able to see clearly for the first time. I see these posts often but I always wonder how they get the eyeglass prescription right for babies?

Normally eye doctors ask you the "is 1 or 2 better" question 15 times but babies can't answer that answer that so how do optometrists get around that?

Is there a method they use that gets the correct prescription or is there a way to tell if the baby is near or far sighted and they just go from there?

submitted by /u/ScienceFreak7
[link] [comments]

Why doesn't the west coast get any hurricanes or tropical storms?

Posted: 24 Mar 2019 05:03 PM PDT

I've been living on the west coast for 18 years and had never had a problem with hurricane, but every fall the east coast always gets a storm.

submitted by /u/DarthTroop
[link] [comments]

Just watched the Sixty Symbols video on LHC and that it has discovered one particle; Is there any major physics theories that it has categorically disproved?

Posted: 24 Mar 2019 08:00 AM PDT

Why can other animals eat raw meat but humans can't?

Posted: 24 Mar 2019 06:38 PM PDT

How do CPU instructions work at the hardware/electrical level?

Posted: 25 Mar 2019 07:44 AM PDT

Hi, /r/AskScience. Longtime reader, first time poster.

I actually have a degree (well, a minor) in CS, but lately I've been getting very interested in the actual physics/electrical engineering involved in computers, particularly the CPU. As all things in CS are conducted at various levels of abstraction, I guess I never really thought much beyond high-level code -> machine code -> CPU instruction set -> logic gates -> back to memory, but now I'm having a hard time wrapping my head around just how this all works, electrically speaking.

My question: how do the electrical signals that physically make up computer code/instructions actually come into being? In CS, we'd imagine executing our code and it would instantly appear in the memory stack, but that's leaving a lot of steps out, I feel. If anyone could help me better understand this phenomena at an electrical engineering level, I'd be very grateful.

I guess I'm ultimately getting thrown for a loop (no pun intended) by the fact that there are no moving parts inside the CPU or RAM; I'm not actually changing anything other than the position of some electrons by "coding," and I'm not all too clear on how this process actually physically takes place.

Thanks in advance.

submitted by /u/upper_crust
[link] [comments]

If I were to magically appear several hundred km above the planet with no orbital velocity, do I experience “weightlessness” or not?

Posted: 24 Mar 2019 11:25 PM PDT

I've seen multiple posts explaining that "weightlessness"'in space is a misconception, and that when we see astronauts in orbit, the apparent weightlessness comes from them being in freecall at 17,000 mph around the planet. Similar, there have been posts that say that the weightlessness that will be experienced by Blue Origin passengers is simply a side effect of being accelerated straight up and then the acceleration ceasing as the capsule enters a coast phase before accelerating back to earth. So my question is : if I was able to instantly appear 100km above the planet's surface with zero orbital velocity, would I experience normal 9.8 m/s/s towards earth and start falling? What if I appeared 200km high? 500km high? 1000km high? Did the Apollo astronauts heading to the moon in a coast phase (no acceleration) experience weightlessness or not?

submitted by /u/ShuffleStepTap
[link] [comments]

How has Jupiter's storm lasted for so long?

Posted: 24 Mar 2019 05:02 PM PDT

Why do black holes have such strong gravitational fields ?

Posted: 25 Mar 2019 12:29 AM PDT

They are formed from a collapsed star core right? I always thought gravitational fields depended on mass not density, why doesn't this work for black holes?

submitted by /u/rqwert2345
[link] [comments]

If you were to wear a completely super hydrophobic body suit, and jump into a pool, would you repel all liquid and just go crashing down to the bottom?

Posted: 24 Mar 2019 10:35 PM PDT

Always wondered this after watching videos of liquids bouncing off shoes and surfaces that were covered in those crazy waterproofing sprays.

submitted by /u/Anti_Axis
[link] [comments]

Why haven’t we found any preserved dinosaur bodies in oxygen-depleted environments similar to bog bodies? (Or have we?)

Posted: 24 Mar 2019 10:14 AM PDT

If energy is never lost, how does the earth get rid of excess energy from the sun?

Posted: 24 Mar 2019 08:42 PM PDT

Why hasn't the earth gotten so hot that life ceases to exist? What protects the earth from absorbing all energy it gets from the sun and holding on to it?

submitted by /u/coolgr3g
[link] [comments]

A geologist was quoted by the BBC as saying "most of the major animal lineages were established in a singular event in the history of life, the Cambrian explosion". How true is this? Was the Cambrian explosion really an event? And did the lineages of all modern animals begin in the Cambrian?

Posted: 24 Mar 2019 08:58 AM PDT

If a black hole sucks something in, Where does it go?

Posted: 24 Mar 2019 03:12 PM PDT

How do lymphatics gain protein from blood?

Posted: 24 Mar 2019 04:40 PM PDT

From what I understand proteins are too large to pass through the walls of capillaries. When tissue fluid enters the lymph vessel it does not contain protein. Where and how does it get into a lymph?

submitted by /u/Meikayah_
[link] [comments]

How do stickers "really work?"

Posted: 24 Mar 2019 03:31 PM PDT

I'm wondering at a microscopic and molecular level. Do the glue molecules get locked in with whatever molecules make up the surface it comes into contact with, do they form bonds, share electrons, that sort of thing?

submitted by /u/clearwall
[link] [comments]

If you have a hypothetical quad-copter that has a 24 hour battery life, is unaffected by the elements and had a clear path. Would it be possible for it to make a full rotation of the Earth while hovering in one place?

Posted: 24 Mar 2019 09:39 PM PDT

How do societies/cultures 'lose knowledge'?

Posted: 24 Mar 2019 04:03 PM PDT

The Greek and the Romans (and I'm sure other cultures too) seem to have had an amazing level of knowledge and wisdom in a wide variety of fields. They created things like the Baghdad Battery, the Antikythera Mechanism, special cements which helped create Aquaeducts that are still around millenia later. Also knowledge about astronomy, the human body and many other things I forgot about (pun bad, but intended). Many things took centuries to be re-discovered.

How does this happen and what else might we have collectively forgotten over time?

submitted by /u/st0pmakings3ns3
[link] [comments]

What are the bumps on a humpback whale for?

Posted: 24 Mar 2019 09:07 AM PDT

I've done a little research and have found out they are called turbicles. They are seemingly for hydrodynamic performance, however, It seems to me that they would be bad for streamlining .

submitted by /u/brit-ish-beef
[link] [comments]

Is there a photoelectric effect that applies to quarks or other small particles? (instead of electrons)

Posted: 24 Mar 2019 08:54 AM PDT

In school we study the absorption of photons by electrons and leaving the atom but could other smaller particles absorb photons like neutrinos and quarks?

submitted by /u/Lucas_The_Man
[link] [comments]

How is the change in magnetic field due to spatial variation different from from motional emf?

Posted: 24 Mar 2019 12:34 PM PDT

Consider the case where a wire is moving in a magnetic field, the source of the magnetic field can either be the loop itself(rail) or an externally applied one (magnet).

If the conductor where to move, the induced emf would simply be the change in flux, which simplifies to ε = -vBL for motional emf where the charges experience a magnetic force on them.

However, if the loop was stationary. And the magnetic field source were to move causing two effects:

  • Change in magnetic field due to it's strength changing.

  • Change in magnetic field due to it's motion , spatial change.

If both effects were occurring this equation can represent it.

How is the second term, only exclusive to the change in magnetic field and not considered to be similar to motional emf?

submitted by /u/tinkenieer
[link] [comments]