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Wikipedia:Reference desk/Archives/Science/2015 April 8

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April 8

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Material for heaviest bat possible

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If I wanted to make the heaviest and most sturdy bat/club possible, what material or element should I use? (Even if it's not easily workable, though hopefully not too radioactive). CesarFelipe (talk) 02:52, 8 April 2015 (UTC)[reply]

Short answer, heavy does does not equal sturdy, so you would have to specify which you want. Others will be along with longer answers. ―Mandruss  03:00, 8 April 2015 (UTC)[reply]
Well, by "heaviest" I mean densest, and by "sturdiest" I mean "resistant to damage/breaking, i.e. not brittle". I've looked up a few materials that are very dense yet brittle, so I don't know if they would work for making a functional bat or not. CesarFelipe (talk) 03:07, 8 April 2015 (UTC)[reply]
Yeah, dense doesn't equal sturdy, either, so you still need to specify which you want. You can't be both densest and sturdiest in the same material. ―Mandruss  03:14, 8 April 2015 (UTC)[reply]
Anything that's really dense probably wouldn't make a functional bat, because you'd barely be able to lift it. Platinum is pretty dense and not brittle. An MLB-sized bat made out of it would be around 32 kg (and cost over a million dollars). Mr.Z-man 03:40, 8 April 2015 (UTC)[reply]
The usual solution to this dilemma is to make the end heavy, but the shaft lighter (as in a mace (club)). Thus you can get a bat with a lot of inertia, yet still light enough to lift. A standard baseball bat is also tapered to get the same effect. StuRat (talk) 06:17, 8 April 2015 (UTC)[reply]
If you are looking for a combination of heavy and strong, you are probably looking for the answer "tungsten".

GilHamiltonTheArm (talk) 07:34, 8 April 2015 (UTC)[reply]

Uranium -- Roger (Dodger67) (talk) 07:41, 8 April 2015 (UTC)[reply]
If you read this by use (an object to be swung to hit something), then "heavy" refers to energy stored in the bat that may be transferred to what it is being hit. Heavy normally refers to the force pulling down on something by gravity, but in this case, it refers to the force being transmitted. That makes me think of tractor trailers. Lateral force is important there. If you are carting around crates of uranium, it isn't a big deal. It just takes more gas to get moving and a longer braking distance to stop. If you are carting around eggs, you have a problem. The liquid makes them harder to move. Similarly, driving a milk truck is hard because the liquid sloshes around. So, imagine a liquid-filled bat. When you strike the ball, the casing of the bat will want to bounce back from the collision. However, the liquid will continue pushing forward. This will create a very heavy feel to the bat. Can this be done? Yes. I already did it in a school experiment years ago with a water-filled wiffle ball bat. We tried water, cooking oil, and spray foam. Cooking oil felt the heaviest when hitting a ball (and we went through a lot of bats and had a large mess because plastic casing is not very effective). I believe that mercury will be the best liquid for this usage. It is very heavy and remains liquid at room temperature. Is there a heavier naturally occurring liquid? I don't know. Next, the casing. Plastic won't work. Wood won't work. You need something that won't dent, won't crack, won't break... I'd begin with a carbon-fiber casing. How about kevlar? I have feeling that will dent. So, I'm stuck on this point. This is where the sturdiness comes in. Once you are swinging a massively heavy mercury filled bat, what kind of case won't dent or crack? 209.149.113.89 (talk) 12:08, 8 April 2015 (UTC)[reply]
Too much sturdiness could work against you. If you see a super-slow-mo of a batter making solid contact, you will see the bat flex slightly. Bats made of ash or hickory are hard but can flex. ←Baseball Bugs What's up, Doc? carrots12:35, 8 April 2015 (UTC)[reply]
Indeed, what you want is efficient energy transfer, there are lots of factors that go into that, not just heaviness and sturdiness. --Jayron32 12:48, 8 April 2015 (UTC)[reply]

Nothing could ever surpass the might of clicky-ba. --Dweller (talk) 15:19, 8 April 2015 (UTC)[reply]

Nonsense. We're talking Mjollnir or the Great Truncheon of Held Wnt (talk) 20:20, 12 April 2015 (UTC)[reply]


Okay... so what material would I want for a bat to hit the hardest and not break or dent? Let's just assume that my strength is not a concern, and neither is cost. It's hard to tell if tungsten would work because certain configurations are sometimes stronger and sometimes brittle. Depleted uranium would sound good if it weren't for the fact that it's still 60% radioactive. Platinum also sounds interesting but again I can't tell whether it's durable enough for a bat because it's not regularly used for making heavy objects (unlike tungsten and uranium which are used for heavy ammunitions). Are there other alloys that would work better? CesarFelipe (talk) 15:47, 8 April 2015 (UTC)[reply]

  • A bat with a titanium skin and a core of U-238, osmium, or lead would make sense. Osmium is the densest naturally-occurring element, but it is toxic, and hugely expensive. The lead core would be the cheapest and safest. But I think you'd have to see baseball players becoming over-muscled weightlifters, a huge spike in injuries to batters, and a few deaths a season due to flying bats. μηδείς (talk) 18:11, 8 April 2015 (UTC)[reply]
You are assuming that the questioner wants to hit a ball with the bat. He hasn't explained what he wants to do. A bat used to punch a hole in a brick wall is much different than a bat used to hit a baseball. What if he wants to hit a ping-pong ball? Again, a very different bat. If you make the heaviest bat possible and it does nothing more than crush and flatten the baseball, that is pointless if the question is actually about hitting a baseball as far as possible. 209.149.113.89 (talk) 18:28, 8 April 2015 (UTC)[reply]
Speculative ref desk questions; a dime a dozen. "You are assuming that the questioner wants to hit a ball with the bat"; priceless. μηδείς (talk) 00:28, 9 April 2015 (UTC)[reply]
Well, if I have to be specific, let's say I want to use the bat as a blunt weapon, so I would want it to be able to hit different kinds of surfaces with force, not just a spot as small as a ball. (And again, let's assume strength and cost are not an issue). CesarFelipe (talk) 19:34, 8 April 2015 (UTC)[reply]
If you're looking for density, you can't beat Quark-gluon plasma ;). On a serious note, I think Tungsten could be a contender. I know you say "price is not a factor" but all things considered, it's only slightly less dense than platinum (19.25 g/cm3 vs 21.09g/cm3) but it's relatively common and cheap, one site I found shows 99.9% tungsten bars cost about $50 per kg, platinum costs over $1000 an ounce. Vespine (talk) 23:09, 8 April 2015 (UTC)[reply]
Quark-gluon plasma? That stuff's for suckers. My bat is made of charged primordial black holes that are electromagnetically confined. It weighs more than the Earth, is that a problem?  ;-) Dragons flight (talk) 17:38, 10 April 2015 (UTC)[reply]

Women's buttocks and handicap principle

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Since there is sexual selection in both genders, I wonder why handicap principle, or maybe rather the sources that are used in that article, gave no examples(that I noticed anyway) of animals from the female sex advertising their fitness through "costly signalling," although certainly signalling exists, whether costly or not. Now buttocks are a sexual signal. But there have been recent articles in the popular media that for some women that have prominent buttocks, it's not only buttock size, but spinal curvature. But spinal curvature seems more definitely costly than buttock size, so it seems that it could be a genuine example, although the popular media doesn't spell that out. The other possibility that comes to mind is large breasts, which can lead to back pain. Of course, one could argue that almost every signal has a cost, but the wikipedia article says it has to be a large enough cost to prove fitness.2601:7:6580:5E3:BD26:AB2F:7045:3132 (talk) 14:48, 8 April 2015 (UTC)[reply]

It's hard to spot a question in there, but I suggest if you want to debate the content of our article, posting at Talk:Handicap principle would be your best option. Of course, if you just want a debate, then you'll need to find another website. --Dweller (talk) 15:13, 8 April 2015 (UTC)[reply]
  • Hmm, it should be easy for someone like you to spot a question in there, even without a question mark. I would denote your reply as intentionally not to the point. Here's a question for you-you describe yourself as former bigshot on a wikipedia board, so do you miss the joy of stifling discussion?2601:7:6580:5E3:944E:5E28:28FE:2E0 (talk) 18:57, 8 April 2015 (UTC)[reply]
Doubt that Dweller's comment stiffled discussion, but your comment definitely did. Nil Einne (talk) 13:35, 10 April 2015 (UTC)[reply]
A term that biologists use is female ornamentation. Here is a list of recent scientific articles on the topic [1] [2] [3] [4]. As for your claims: buttocks may indeed be a sexual signal (for both human males and females), but they also serve many other purposes. Have a look at an image search for say the 100m dash - those muscles help us run. If you look at a google scholar search for /costly signaling human/ [5], you'll see that almost all the scientific work is about cultural signaling, not morphological signaling. SemanticMantis (talk) 15:42, 8 April 2015 (UTC)[reply]
I was under the impression that what you're really seeing is larger hips - which correlates directly with the ability to successfully give birth - which would be an obvious indicator of reproductive success what will be selected for. It's easy to imagine spinal curvature being a part of that too. SteveBaker (talk) 17:27, 8 April 2015 (UTC)[reply]
  • It's called sexual selection. Men who mated with unhealthy females who consumed their fat reserves and had small behinds would be less likely to conceive, and more likey to loose a child due to malnutrition. Hence a gene that makes men prefer curvaceous women would make sense, even if otherwise, large behinds might be a handicap in running to escape a predator. That prerence would result in women's buttocks becoming larger, as the larger the butt, the more eager suitor and healthy babies. μηδείς (talk) 00:18, 9 April 2015 (UTC)[reply]
There have been some amusing and interesting reports on this in the press lately ([6][7] but trying to chase down any real research out of them is a bit frustrating. I ought to look harder but I'm having a hard time picturing what kind of study would actually have been done to get a convincing proof. Still, any excuse is a good excuse :) Wnt (talk) 19:19, 11 April 2015 (UTC)[reply]

calorific value of carbon monoxide

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I am performing an experiment that needs the calorific value of gases produced from combustion of 1kg of coconut shell.I tried to google it but could not find any useful detail.Atleast ,a simplistic approach to estimate the required value is cordially welcome.115.241.9.191 (talk) 17:06, 8 April 2015 (UTC)[reply]

I don't know what coconut shell is made of precisely, or why it would produce carbon monoxide during combustion, but maybe Standard enthalpy of formation is helpful. From the table in that article one can see that the energy of 1 mol CO is 110.5 kJ lower than the combined energy of1 mol of elementary carbon and 1 mol of elementary oxygen (i.e. 0.5 moles of O2), meaning that converting these into 1 mol CO will produce 110.5 kJ in heat. - Lindert (talk) 17:19, 8 April 2015 (UTC)[reply]
http://nvlpubs.nist.gov/nistpubs/jres/6/jresv6n1p37_A2b.pdf says 283 kJ/mole at 30 degC. SteveBaker (talk) 17:22, 8 April 2015 (UTC)[reply]
And just to be clear, that is the heat produced by converting 1 mol of CO into CO2, according to CO + 1/22 -> CO2, so it's the difference between the standard enthalpies of CO and CO2. - Lindert (talk) 18:26, 8 April 2015 (UTC)[reply]

Orgasm

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Do men and women experience the same overall feelings/sensations when they orgasm? — Preceding unsigned comment added by 117.167.237.194 (talk) 23:43, 8 April 2015 (UTC)[reply]

Wikipedia has an article titled Orgasm which has links to further articles that will help you in your research. Feel free to read that article, and follow links from there and see where it leads you. --Jayron32 23:55, 8 April 2015 (UTC)[reply]
Per that article, pretty much the same. A bit longer for the ladies, generally, and more of a comedown for the gentlemen. InedibleHulk (talk) 00:00, 9 April 2015 (UTC)[reply]
We have no current way of directly measuring qualia, subjective conscious experience. Consider, how do we know that what I see and name as red is not experienced by another person as what I would name green? The color spaces in our heads might be flipped, so that white is black and blue is yellow. As long as we agree to call the same things by the same names, consistently, there would be no way to know that our subjective experiences were reversed.
We do know that people with color blindness have a different experience fro that of trichromats, but only because we notice that the words we use conflict, or the distinction is lost on the dichromat. Even then, we don't know if dichromats view both red and green as red, or as green, or as violet, for that matter.
Assumptions based on physiology say that since the neurotransmitters are the same, the experience must be similar, but we have no idea at what level of processing qualia arise; molecular, cellular or at the level of one or more parts of the brain.
We do know that gene therapy for color blindness has worked in animals, but it has not yet been tried in humans. We will learn a lot if they report that everything appeared red, or green, or brown before, but now I still see red, but I also see a new color, the one people were always calling green. μηδείς (talk) 00:12, 9 April 2015 (UTC)[reply]
For the classical answer, see "Of ten parts a man enjoys one only." -- ToE 00:28, 9 April 2015 (UTC)[reply]