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Sunday, January 10, 2016

Does every pure chemical have a triple point?

Does every pure chemical have a triple point?

Does every pure chemical have a triple point?

Posted: 09 Jan 2016 02:51 PM PST

A triple point is a temperature and pressure where the substance is simultaneously a solid, liquid and a gas

Are triple points for some substances predicted theoretically but hard to test?

submitted by timpattinson
[link] [193 comments]

How much did the invention of the nuclear bomb affect Carbon 14 dating?

Posted: 09 Jan 2016 04:34 PM PST

Why is the Higgs Boson listed separately from the other Gauge Bosons in the Standard Model?

Posted: 09 Jan 2016 04:58 PM PST

Why do small objects stick to our fingers when we push down on them?

Posted: 09 Jan 2016 11:16 PM PST

There was a staple on the ground, so pushed down on it with my finger, and it stuck to my finger for a short time (not puncture). Why does this happen?

submitted by KelpyG
[link] [11 comments]

Why can't we create other beneficial molecules from the sun, like we do with Vitamin D?

Posted: 09 Jan 2016 01:52 PM PST

Many organisms can photosynthesize and we need sun exposure for vitamin D. Why can't we then harness the sun for ourselves to synthesize other molecules or even just harness the energy of the sun in a manner analogous to photosynthesis? Thanks!

submitted by jish_werbles
[link] [20 comments]

What exactly is ferroelastic domain switching and how does it act as a toughening mechanism in certain ceramics?

Posted: 09 Jan 2016 01:26 PM PST

Effect of genes working with other genes?

Posted: 09 Jan 2016 11:01 AM PST

What amount of the formation of organisms is directly from the coding of DNA vs something only happening when the gene is expressed in an organism?

Ex: If we copy genes from one animal to another could we unknowingly change the outcome of the gene because gene X only looks like X if it is used with gene Y. Could we use RNA to tell us if gene Y and gene X are being used or would X gene only be shown as active because it is the only one being produced.

submitted by TheKillersRock
[link] [12 comments]

When space expands, do objects get bigger?

Posted: 09 Jan 2016 08:03 AM PST

It seems to me that in an expanding universe, objects would enlarge in tandem with space and so the apparent distance between 2 objects should stay the same over time barring any other movement. Obviously, this can't be the case, otherwise we wouldn't be able to notice the expansion in the first place, but do objects change in size at all? How does the expansion of space affect the size and internal structure of objects?

submitted by rikeus
[link] [39 comments]

Why does my body have the same freckles/birthmarks throughout my whole life?

Posted: 09 Jan 2016 10:17 PM PST

My skin cells regenerate, though I'm not sure at what pace. So why don't freckles and birthmarks disappear with time?

submitted by remembuary
[link] [5 comments]

Have any wind turbines been able to break the Betz limit?

Posted: 10 Jan 2016 06:46 AM PST

I've seen multiple claims of new wind turbines that due to some characteristic, usually design, can output more energy than traditional wind turbines. Are these all hoaxes?

submitted by primalMK
[link] [comment]

Is it possible to catch 2 different cold viruses at the same time?

Posted: 09 Jan 2016 11:24 AM PST

If cold viruses are constantly mutating and always changing, doesn't that mean you can catch a common cold from one person and then catch another version of the common cold from somebody else? If I get over a cold (and so my body is well-equipped to fight that particular virus), am I safe to be around other people with the common cold, or could I catch it again just as easily?

submitted by TheDrunkPianist
[link] [6 comments]

Can sign language have an accent?

Posted: 10 Jan 2016 03:02 AM PST

Additionally, does sign language changed based on the country of origin?

submitted by Azimuth2888
[link] [comment]

Demagnetisation curve - what happens just after coercivity field strength if you'd turn off the external magnetic field?

Posted: 10 Jan 2016 01:32 AM PST

Here is an example of a demagnetisation curve. Let's assume we start somewhere in positive H-direction (e.g. 100 A/m) and slowly decrease the external field (strength).

If we would turn it off (H=0), we would still have a flux density B of B_R (remanence).

If we decrease H further (H now < 0) and turn it off, B would still be B_R.

What happens if we decreased H to "-H_Saturation" < H < H_C and we turn it of? Would it still go back to B_R? At what point will it fall to -B_R? Does the material have to be saturated in negative direction?

Thanks for your help.

submitted by Boernii
[link] [comment]

How (where, when) exactly does limescale deposit in electric water kettles during boiling process?

Posted: 09 Jan 2016 05:22 AM PST

As I understand, there is an equilibrium in the water: Ca2+ + 2HCO3- ⇋ Ca2+ + CO32− + CO2 + H2O where balance moves right as CO2 leaves the boiling water.

Does it happen everywhere in the water? How quickly does the CaCO3 fall to the bottom? Why is there limescale on the walls (why doen't it fall to the bottom of the kettle)?

(context: I want to make a tea boiler+infuser, where i could thown away any limescale each time alongside with the used tea leaves.)

submitted by ervion
[link] [5 comments]

Quantum fluctuations after big bang?

Posted: 09 Jan 2016 06:25 AM PST

I was just wondering what the actual mechanism of these "quantum fluctuations" that ive read about are. As i am understood they are some how responsible for fluctuations in particle density in the very early universe which caused stars, galaxies etc. to form, and i was just curious what they actually are. Thank you.

submitted by Irtzna
[link] [8 comments]

Why do eggs take longer to boil at higher altitudes?

Posted: 09 Jan 2016 12:46 PM PST

I get that it takes longer for water to boil at higher altitudes. And I get that the boiling point of water changes, and I get why. What I don't get is this: If you're applying the same amount of heat (energy) into the system, doesn't the egg get cooked ("boiled") at the same time anyways? does boiling water really transfer heat that much more efficiently? Thanks.

submitted by Amaterashu
[link] [8 comments]
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Saturday, January 9, 2016

Do protons and neutrons maintain distinction inside the nucleus of an atom or do they combine into a quark soup?

Do protons and neutrons maintain distinction inside the nucleus of an atom or do they combine into a quark soup?

Do protons and neutrons maintain distinction inside the nucleus of an atom or do they combine into a quark soup?

Posted: 08 Jan 2016 06:10 PM PST

Do the three quarks of a proton/neutron stay bound together strongly while acting as the nucleus of an atom? Protons and neutrons are made of the same two quarks so it seems logical to me that they may just form a quark soup in the nucleus. Any reading material would be appreciated. Thanks!

submitted by 0x00000194
[link] [77 comments]

Is charge always conserved?

Posted: 09 Jan 2016 05:45 AM PST

I know the fundamental principle of charge conservation, but I am wondering if there is any situation in which it could be seen differently (something similar to "mass conservation" and the Energy-Mass relationship)

submitted by anper29
[link] [9 comments]

Are the blueprints for building a penis solely on the Y chromosome?

Posted: 08 Jan 2016 01:13 PM PST

What was the extent of glacio-isostatic depression in the last ice age?

Posted: 09 Jan 2016 04:03 AM PST

How much did the earths crust warp (distance-wise) during the last ice age when covered with up to 1500m if ice? I am sure there is a way of working it out, but cannot find a solution!

submitted by Oisc
[link] [1 comment]

Can laws of physics in the Universe change over time?

Posted: 08 Jan 2016 12:55 PM PST

Would a person weigh more at the pole than at the equator?

Posted: 08 Jan 2016 06:10 PM PST

I ask because it seems the centrifugal force would be greater at the equator than the the pole, effectively reducing the force of gravity at the equator. This question is assuming the Earth is a perfect sphere (which I know is not the case).

submitted by I-Am-McLovin
[link] [12 comments]

How is gravity "weak"? What scale are we using to compare the forces?

Posted: 09 Jan 2016 03:37 AM PST

I've heard the example of being able to counteract the gravity of the entire earth merely by picking something up, but that is a subjective description of weak. In what way can four forces be compared that makes us wonder why gravity is weak, and why would we expect them to be similar? In other words, why do we need an explanation as to its relative weakness? I hope this question makes sense...

submitted by Forsyte
[link] [8 comments]

Is a 'randomly' generated real number practically guaranteed to be transcendental?

Posted: 09 Jan 2016 05:27 AM PST

I learnt in class a while back that if one were to generate a number by picking each digit of its decimal expansion randomly then there is effectively a 0% chance of that number being rational. So my question is 'will that number be transcendental or a serd?'

submitted by suffy309
[link] [3 comments]

What do we know about human intelligence? Is it related to intrinsic strengths, skills, or mental capacities?

Posted: 08 Jan 2016 06:52 PM PST

For example: strong short term memory, strong long term memory, high sensory sensitivity/awareness. Are there different modalities of general intelligence?

submitted by Whatisthemind
[link] [9 comments]

Does the Moon at some point enter Earth's magnetopause?

Posted: 08 Jan 2016 04:55 PM PST

So I was reading a NASA article about what happend when the Moon interact with the magnetotail, it was interesting so I begin to read a bit about the magentic field/magnetosphere subject and I ended up with a confusion...

At some point I got that the magnetopause was the border of the magnetic field and that in the non-facing-sun side (the tail) it was max. 15ER. Then I read that the Moon orbits at like 60ER, and then it says in another article that the magnetotail goes to 200ER.

So at first I thougt it was refering to the magnetosheath but at the end I ended up confused.

Where does the moon enter in the way he NASA article's refers to?

Side note, I'm not a native english speaker so sorry for any gramatical/ortografical mystake.

submitted by Arquitect_Of_Noyla
[link] [3 comments]

In Deal or No Deal, when you get to the end (just two unopened cases left), you're given the option to switch. If the $1M suitcase is still in play, does the monty hall problem apply... at 96% probability?

Posted: 08 Jan 2016 08:43 AM PST

As I understand it, the Monty Hall problem involved 3 doors with on prize.

When you select a door, you have a 1/3rd chance or 33.33% probability of having the prize, and the other doors represent a 66.67% probability.

When one of the other doors is opened and not a winner, the remaining door still represents a 66.66% probability.

In Deal or No Deal, there are 26 suitcases. As you progress through the game, cases are opened and their values revealed.

When you first select a suitcase, your suitcase has a 1 in 26 chance of containing $1M, or a 3.8% chance. And the other suitcases represent a 96.2% chance of holding the big prize.

If you get down to the final two (your selection, and one other on stage), and the $1M hasn't been hit. Does it still represent a 96.2% probability of containing $1M?

submitted by CobraCabana
[link] [54 comments]

Is our moon boring?

Posted: 08 Jan 2016 10:02 AM PST

From an astronomy point of view, it seems there is way cooler stuff happening on other moons in our solar system. For example, Ganymede has its own magnetic field, Titan has an atmosphere that is similar to some planets, Io has its highly volcanic surface, etc.

So, what is the popular opinion of our moon in the astronomy community? Is there much reason to go there and study it or do we know what we're going to see?

submitted by Erik_2
[link] [24 comments]

Can a central force produce different closed orbits?

Posted: 08 Jan 2016 11:02 PM PST

I saw this on /r/space and was interested in the mechanics of a geocentric solar system.

Could a central force produce two different closed curve orbits other than a circle and ellipse? Could an object subject to a central force orbit the source of the force on a cardioid, or any other closed curve, for example?

submitted by P_S_Laplace
[link] [6 comments]

How does electromagnetic shielding work?

Posted: 08 Jan 2016 04:12 PM PST

I've read the wikipedia article here:

https://en.wikipedia.org/wiki/Electromagnetic_shielding

But I can't "picture" how the mechanism of having a cage-like piece of metal with holes would affect electromagnetic waves. EM waves are caused by photons, right? And the photon "wave" doesn't actually change positional amplitude when the wave amplitude changes, right? Photons essentially travel straight.

So if you have 10E18 or however many photons per square meter traveling at a shielded cage, wont they just travel straight through the holes? Why would there be a frequency dependence on whether or not photons will make it through different size holes?

submitted by whatamidoing11
[link] [4 comments]

Why do the bubbles on the surface of a drink (coffee, for example) seem to attract one another?

Posted: 08 Jan 2016 08:19 AM PST

I've noticed that not only do bubbles appear to "gravitate" towards each other, but they also like to form rings around the inside of the mug, instead of all clumping together or floating somewhere in the middle.

submitted by broinabaja
[link] [3 comments]

Do other species have different blood types?

Posted: 08 Jan 2016 10:29 AM PST

If a bowling ball was hollow, but had the same mass, would the physics of bowling be any different?

Posted: 08 Jan 2016 10:42 AM PST

Same question for the pins as well.

submitted by dapieman57
[link] [4 comments]

What causes the pressure changes over the Pacific Ocean that causes El Nino?

Posted: 08 Jan 2016 04:55 PM PST

Hi, I recently became interested in El Nino and looked at what causes it. I found that due to pressure changes in the east and west Pacific, trade winds weaken. This slows the ocean currents and warmer waters flow east - increasing precipitation in the western side of the Americas. But I couldn't find any explanations/theories that show what causes the pressure changes in the first place. I was wondering if it had something to do with the sun / earths orbit, or any other factors? If anyone has a response, could you include credible links/sources? Thanks!

submitted by novice_meditator
[link] [comment]

Why did my apple juice only freeze after I poured it in a cup? (see pic inside)

Posted: 08 Jan 2016 08:50 AM PST

So I accidentally left a bottle of fizzy apple juice ("Apfelsaftschorle") in the freezer for a day. When I took it out, it was still liquid. Then I poured some into the cup and it started freezing.

In this picture you can see the cup. At first everything was liquid (like the bottom) but the rapidly froze in a bottom-up manner. Why? Has it something to do with that before, it was colder than 4°C?

submitted by cyberonic
[link] [6 comments]

How many distinct arrangements are there of 100 dice in 6 different colours?

Posted: 08 Jan 2016 10:01 AM PST

See image here:

http://img.dxcdn.com/productimages/sku_8667_1.jpg

How many different TO THE HUMAN EYE 10x10 squares can we arrange? Let the number of dice of each colour be a,b,c,d,e,f so one constraint is a+b+c+d+e+f =100.

EDIT: "To the human eye" means that each arrangement is different for an observer from the same position - ie orientation of 2,3 and 6 die faces matters, and entire rotational symmetry of the 10x10 square matters. Simply - how many different arrangements of such a 10x10 square are there?

submitted by escherbach
[link] [13 comments]

Question about anti matter-matter annihilation?

Posted: 08 Jan 2016 07:56 AM PST

Does anti matter annihilate with any matter or just with its exact opposite? As in, would antihydrogen be safe in containment of pure carbon for example and only annihilate with hydrogen or does it react to everything? If it does annihilate with all normal matter, what would happen if we pushed antihydrogen to say uranium (or any other really heavy element)?

submitted by Ergroil
[link] [6 comments]
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Friday, January 8, 2016

AskScience AMA Series: I'm Elana Simon, a liver cancer survivor. At 18, I published gene sequencing research about my cancer in the journal Science. AMA.

AskScience AMA Series: I'm Elana Simon, a liver cancer survivor. At 18, I published gene sequencing research about my cancer in the journal Science. AMA.

AskScience AMA Series: I'm Elana Simon, a liver cancer survivor. At 18, I published gene sequencing research about my cancer in the journal Science. AMA.

Posted: 08 Jan 2016 05:00 AM PST

When Elana Simon was 12, she was diagnosed with a rare liver cancer, Fibrolamellar hepatocellular carcinoma, or FL-HCC, which affects mostly young people. After surgical treatment, Elana used her computer skills to create a registry that could help researchers (including her own father, Sandy Simon, of The Rockefeller University) to deepen their understanding of the mysterious cancer that threatened her life. In 2014, Elana (then 18), Sandy, her surgeon and others published research in the journal Science (link(. Their research suggested a mutation that leads to that cancer.

Today, Elana is a 20-year-old sophomore at Harvard University and vice president of the Fibrolamellar Registry (link). She's been recognized by the White House, by science and medical communities, and local, national, and international media. She and her father want to spread the word about their research and answer any questions Reddit users might have. Ask them anything!

TL;DR At 18, Elana and others crowdsourced tissue samples to study the genetics of her rare type of cancer.

Video explanation by Elana: http://www.aaas.org/content/common-chimera-rare-tumor

The AMA is being coordinated by AAAS, the American Association for the Advancement of Science, which publishes the journal Science. The AMA will take place starting at 12 PM EST.

Associated Press story: http://bigstory.ap.org/article/teen-helps-scientists-study-her-own-rare-disease

submitted by AskScienceModerator
[link] [24 comments]

Why are Autistic Spectrum Disorders far more prevalent in males than in females?

Posted: 07 Jan 2016 11:47 AM PST

Is the VASIMR plasma engine as good as they say?

Posted: 08 Jan 2016 12:33 AM PST

I saw this click bait on Facebook about a VASIMR plasma engine that says it's the key to propulsion once in space. /r/AskScience, please explain!

submitted by ddogreddit
[link] [4 comments]

Am I heavier if I fill my lungs with air? (as measured by a scale)

Posted: 07 Jan 2016 08:05 AM PST

Would there be a difference in weight? (Assume a highly precise measuring device, so even if it's very small)

submitted by d6x1
[link] [35 comments]

Cement is made from fly ash; how will a shift from fossil fuels affect industries which depend on their waste?

Posted: 07 Jan 2016 06:50 AM PST

Why can mosquitoes transfer malaria but not AIDS?

Posted: 07 Jan 2016 04:06 PM PST

When new elements are created in the lab, why do we smash together individual atoms instead of just smashing two bigger clumps together?

Posted: 07 Jan 2016 11:39 AM PST

Surely if our goals is to perform thousands and thousands of collisions, wouldn't it be easier to collide larger clumps of atoms than single atoms? Or is it something about the acceleration process that prevents us from doing that?

submitted by quatrevingtneuf
[link] [11 comments]

What makes an element worth of the periodic table?

Posted: 08 Jan 2016 12:11 AM PST

Ask this chemist about creating new elements http://www.particlenews.com/n/01YsmP1e

I'm trying to wrap my brain around what actually makes a new element an element? Is antimatter not considered an element? Does the element have to be a certain substance? What are the criteria? Not all elements are naturally present, so does that make a difference? What does it take then y to make a "new" element?

submitted by [deleted]
[link] [9 comments]

Why do some stars appear to flash red/blue whilst others don't?

Posted: 07 Jan 2016 04:41 PM PST

How come when you and a friend get out of a loud venue such as a concert and you can't hear as well your friend and you yell at each other when talking, instead of talking in your normal voice. ?

Posted: 07 Jan 2016 08:04 PM PST

Is it possible for some people to have a more/less saturated vision than other people?

Posted: 07 Jan 2016 07:59 PM PST

For example, can some people see more saturated colors than other people can?

submitted by Dragonbourbon
[link] [5 comments]

Why are there different programming languages? Are they used in different ways, or is it more of a preference by the creator?

Posted: 07 Jan 2016 12:28 PM PST

I have no experience with coding of any kind... I know of a few languages though, BASIC, Java, Python, C++, but I'm curious why there are so many?

What similarities do they share and what differences do they have? How/why did different languages come about?

submitted by ChrisGnam
[link] [18 comments]

Why is it that my dishwasher can't remove tea stains from cups, but a small bit of rubbing with a dish sponge takes them off easily enough?

Posted: 07 Jan 2016 07:11 AM PST

In more detail - it seems that dishwasher tablets are able to successfully clean a lot of other food residues that are more difficult to clean manually - why aren't tea stains removed so easily?

submitted by T_at
[link] [14 comments]

What is the maximum distance one can vertically suck water, if there is one?

Posted: 07 Jan 2016 03:42 PM PST

If I ate a malignant cancerous tumor, does that increase my risk of getting cancer or is the genetic material destroyed by digestion?

Posted: 07 Jan 2016 02:40 PM PST

How much of the human brain can be gotten rid of before it stops functioning?

Posted: 07 Jan 2016 01:20 PM PST

I was just thinking about the scene in Silence of the Lambs, (I'm sure most of you know what I'm referring to, but for those who don't, http://imgur.com/gallery/1nLKDlJ.), and it got me thinking.

Let's say you are sitting in a professional brain surgeon's chair and he has the task of removing as much of your brain as possible, while still keeping you alive. How much would be left? What functions would you still have intact? Could you leave the OR afterwards?

submitted by awesomeguy4018
[link] [6 comments]

How does turning on AC help defog car window?

Posted: 07 Jan 2016 05:02 PM PST

I've heard that AC "Pulls moisture out of the air, as the air passes over the cold coil"

Doesn't AC actually heat air when the car is cold?

And if AC coils are placed after the air gets warm, wouldn't that just make air colder and not loose any of it's water.

Are any of my claims true. And is this the way AC help defog the windows?

submitted by bertoncelj1
[link] [6 comments]

NASA reported that solar winds were responsible for stripping Mars of it's atmosphere. If we did terraform Mars, why wouldn't the atmosphere just be stripped away again?

Posted: 07 Jan 2016 08:20 AM PST

Have we ever seen a star orbiting a black hole pass behind it on our plane of view? If so, what did we see, or expect to see?

Posted: 07 Jan 2016 10:04 AM PST

Why, in electrolysis, do bubbles only form on the electrodes?

Posted: 07 Jan 2016 05:43 PM PST

If you have two metal plate electrodes, and you use them to electrolyze water, bubbles form on the plates. However, isn't there an electric field throughout the area between the? Why isn't the water split at any point between the plates?

submitted by TortugaTerritory
[link] [3 comments]

Since bismuth has been discovered to be radioactively unstable, is there any assurance that isotopes of other, lighter elements are stable?

Posted: 07 Jan 2016 02:45 PM PST

Can Cnidarians do associative learning?

Posted: 07 Jan 2016 02:34 PM PST

I've seen few attempts to answer this question in the literature except for one study here (http://www.sciencedirect.com/science/article/pii/0031938475902590). Does anyone in the field know if this was ever repeated and reproduced?

submitted by jdenniso
[link] [2 comments]
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