Science desk
< June 23	<< May \| June \| Jul >>	June 25 >

Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

June 24

Drinking sub-zero alcohol

I've heard that strong brandy won't freeze even at -20°C. If I were to keep a bottle at say -5 or -10°C would my mouth and throat start to freeze when drinking it considering we're mostly made of water? 78.0.252.164 (talk) 13:07, 24 June 2016 (UTC)[reply]

Frostbite of the tongue would give you a hint to stop your experiment. AllBestFaith (talk) 13:35, 24 June 2016 (UTC)[reply]

Your drink might not be cold enough to cause serious damage - but there have been serious consequences from a Liquid nitrogen cocktail Wymspen (talk) 14:02, 24 June 2016 (UTC)[reply]

Hehe, should've remembered to ask Russians :D 78.0.252.164 (talk) 21:02, 24 June 2016 (UTC)[reply]

Why do you want to drink it so cold? You will not experience the bouquet (the whole point of a snifter is to warm the liquor in ones own hands to release the bouquet ) If you want to drink sprites very cold, then go for low quality spirits like American Bourbons. Made very cheaply from maize (the US call it Corn -but the results are the same). --Aspro (talk) 15:28, 24 June 2016 (UTC)[reply]

Sounds like someone has not had much exposure to Bourbon, or at least not the right kinds. Anyway, vodka is the spirit that is commonly served ultra-cold. SemanticMantis (talk) 16:16, 24 June 2016 (UTC)[reply]

Depends on the liquor definitely. I find that whiskey is best drunk cold, except maybe for Jim Beam and similar. But then again I don't like Jim Beam much 78.0.252.164 (talk) 21:02, 24 June 2016 (UTC)[reply]

http://msgboard.snopes.com/message/ultimatebb.php?/ubb/get_topic/f/108/t/000648.html --Guy Macon (talk) 17:39, 24 June 2016 (UTC)[reply]

Probably one key reminder from that discussion is that freezers are often -15°C or lower, so anything store in them for long periods, like ice cream, sorbets, ice blocks and ice cubes are likely to be at those temperatures. Yes they're solid so won't make so good contact with the lower part of the mouth (although probably better with the upper part). And even for those which are normally eaten frozen like ice blocks, ice cream and sorbets it's normal to let them warm up slightly and eat them slowly. Still I'm sure many people even here have experience eating at least one straight from the freezer and gulping it down. As for ice cubes, I'm sure some people here have putten an ice cube straight from the freezer into their mouth, some have even accidently or intentionally swallowed one. The biggest danger would likely be choking. Heat capacity and quantities are relevant, I'm sure you could cause some injury due to the cold if you tried hard enough but generally there's no reason to think the drinks are going to be generally different. (The earlier points along with heat transfer don't seem to have been considered in the discussion about air temperatures on Snopes.) Notably, even if the alcoholic drink did freeze you could always make an ice cube or block out of that just like with water, in other words there's even less reason to think of the non freezing drink as special. Perhaps if you had something which froze at exactly -15°C (or whatever) then enthalpy of fusion would be relevant but that doesn't seem to be what was referred to and I don't think alcoholic drinks are likely to freeze or melt in a simple way anyway. P.S. It's possible Leidenfrost effect would make some difference, or there would be some effect of an insulating layer, but I don't think it's clear that will be significant for water or water mixtures or ice cream at the temperatures involved. Nil Einne (talk) 19:19, 24 June 2016 (UTC)[reply]

Thanks guys. FWIW ice cubes are fine with me even straight out of the freezer, the worst that can happen is tongue getting stuck anyway, I was more worried about cold liquid coating and freezing the whole mouth, but yeah I suppose it's not a danger at these quantities and temperatures especially with the summer heat here.78.0.252.164 (talk) 21:02, 24 June 2016 (UTC)[reply]

Very cold beverages can actually cause a burn in the mouth or throat. And such burns can lead to cancer, according to the WHO. See here. Akld guy (talk) 00:14, 25 June 2016 (UTC)[reply]

I am of Polish ancestry and can say first hand that it is very common to keep vodka in the freezer and drink shots of it immediately from the freezer, without any "freezer related" injuries. I think the "heat capacity" thing might be the key here, even half a glass would not be enough to "freeze" anything on the way down, more than half a glass at a time and I dare say you need to start worrying about things 'other' than your throat freezing. Vespine (talk) 00:31, 27 June 2016 (UTC)[reply]

Number of leads for a segmented LCD display

For 1/2 duty 1/2 bias segmented LCD displays:

1. 14 segments requires 9 pins

2. 18 segments requires 10 pins

What's the formula here?

My best guess so far is ceiling( # of segments / 2 ) + 2. Not sure if that's right or not. Johnson&Johnson&Son (talk) 15:06, 24 June 2016 (UTC)[reply]

TI's datasheet: http://www.ti.com/sc/docs/products/micro/msp430/userguid/ag_14.pdf

You need to loook for "2MUX", also "3MUX" and "4MUX". Note that this is LCDs, not LEDs. Andy Dingley (talk) 18:59, 24 June 2016 (UTC)[reply]

Thanks!

In their formula, Integer [2 + (#-of-segments/2)], is Integer() rounding up or down? Johnson&Johnson&Son (talk) 02:42, 25 June 2016 (UTC)[reply]

It would be rounding up. You need the connection whether you have one or two segments connected to it. Andy Dingley (talk) 09:12, 25 June 2016 (UTC)[reply]

Energy efficiency and speed of submarines and ships

Which can be faster and are energetically more efficient? Ships or subs? That is, comparing two which can hold the same cargo, not directly two which have the same size. --Llaanngg (talk) 19:00, 24 June 2016 (UTC)[reply]

A hint from nature is that the whale, the greatest sea mammal, travels long distances underwater rather than on the surface. See Whale#Locomotion. AllBestFaith (talk) 19:51, 24 June 2016 (UTC)[reply]

Nice hint, but there might be other non-speed, non-efficiency related reason for this. The skin or eyes could be too sensitive to travel on the surface, more food could be available deeper in the ocean, navigation might be easier underwater. --Llaanngg (talk) 23:51, 24 June 2016 (UTC)[reply]

FWIW: asked & answered on 'Yahoo! Answers' → [1] --107.15.152.93 (talk) 23:12, 24 June 2016 (UTC)[reply]

I am trying to find more reliable sources than Yahoo Answers, but thanks anyway. --Llaanngg (talk) 23:51, 24 June 2016 (UTC)[reply]

Submarines, because much of the losses are in creating waves on the surface.

In the 1960s, giant cargo submarines were studied conceptually to exploit this. However a long-submerged submarine needs nuclear power and the fuel elements for a compact reactor are also a gift for weapons production. Such a cargo submarine might also make a viable missile carrier. So, no cargo submarines.

The closest we got, in a way, was the bulbous bow which is also quite an efficient way to make a hole in water. Andy Dingley (talk) 00:01, 25 June 2016 (UTC)[reply]

Surface ships spend about half of their power to create waves. A submarine makes no waves, provided it's at a large depth compared to its diameter. Skin friction is lower for a submarine too, as it has a smaller wet hull area for the same displacement, assuming a typical beam:draft ratio for the surface ship. So the submarine is more efficient. However, a ship's size is often limited by draft. Most cargo ships are designed with the largest possible draft that still allows them to go where they have to go. At a given draft, a submarine has, because of its cylindrical hull, much less displacement and therefore loading capacity than a surface ship, which makes it less efficient. Then there's the limited safety of submarines, the nuclear material and the difficulty of loading/unloading any type of cargo except fluids or granular material, which makes them only usable for time-insensitive bulk. Using a cheap and slow surface ship works better for bulk.

Submarines have been proposed for transporting crude oil out of the Arctic, where they have the advantage of being capable of diving under the ice. But by first consuming the oil from warmer areas of the planet we managed to meld the ice cap, so there is no longer a need for that. PiusImpavidus (talk) 08:41, 25 June 2016 (UTC)[reply]

Portion size of food and nutrients

Recently, I watched Sugar Coated (2015) documentary. It was about the excessive use of sugar in the food industry to make food taste better and to compensate for the decrease in fat in order to increase sales. One man says that one piece of the fruity candy thingy has as much sugar as a candy bar or a bowl of strawberries, and argues that the vendor is marketing the candy as fruit. I paid attention to the bowl of strawberries part. I have personally eaten greater quantities of strawberries or grapes before. Counting by the amount of sugar consumed, is it possible to overdose on sugar by gorging on fruits while watching TV? 66.213.29.17 (talk) 19:41, 24 June 2016 (UTC)[reply]

Define "overdose on sugar". --Guy Macon (talk) 20:34, 24 June 2016 (UTC)[reply]

According to our article, the LD50 of sugar is 29.7 g/kg, so, a person weighing about 100 kg (rather above average for the general adult population), would need to eat three full 1 kg bags of sugar before it had immediate consequences - I doubt that's practically possible with pure sugar, let alone any sort of fruit. Of course, smaller amounts increase the risk of dental and medical problems, and the OP should see a doctor if they're worried about their health, but an actual acute overdose is unlikely. See Sugar#Sources for the numbers on various types of fruit. Tevildo (talk) 20:40, 24 June 2016 (UTC)[reply]

LD50s can vary quite a bit depending on the organism (as well as other factors about the population), I doubt we have an LD50 for sugar for humans. Maybe more important, remember LD50 is when half of the population is killed and there's pretty much nothing where half the population dies of only and precisely at a certain dose. So even if the LD50 for humans were as stated, many 100kg people are going to have immediate consequences before 3kg, including death. (Death isn't the only immediate consequence, you could have vomiting for example.) However empirical evidence would suggest if we ignore diabetics, the figure for immediate consequences would be quite high. Nil Einne (talk) 19:25, 25 June 2016 (UTC)[reply]

Hmmm... 64% of the carbohydrate calories in strawberries are sugars: fructose, glucose, and sucrose. But the glycemic index is 40, i.e. a low glycemic index food that is unlikely to cause blood sugar issues in diabetics. [2] There must be some crucial little detail here I'm not understanding... Wnt (talk) 20:46, 24 June 2016 (UTC)[reply]

If you're asking why the glycemic index is low, it's because fruit contains a buttload of fiber. --71.110.8.102 (talk) 00:13, 25 June 2016 (UTC)[reply]

And because strawberries consist of 91 percent water, meaning that there are little carbs in them. Sjö (talk) 06:45, 25 June 2016 (UTC)[reply]

Finding a cat in a big house

Hello all,

My wife and I are cat people. Currently we have one cat but she is young, small, spunky, rumbustious and very smart. We love her to death. Her objective is to get out of the house and roam outside but she is a house cat. Despite our best efforts she has managed to escape about a dozen times every time for a brief period except one, when we could not find her for about five hours. My wife went totally nuts, accusing me of neglect and threatening me with the hell's fire. Apparently she slipped between my feet when I was leaving home. It is not why I am posting though.

She has a habit of disappearing in the house for sleep. My wife sometimes spends an hour looking for her because she suspects that the cat might have escaped. I am worried also. Our house is not clattered by any means but it is impossible to find her. Then she would show up as nothing happened, almost smiling.

I know there are photo-cameras used to snap pictures of wild animals in nature during the night and I want to explore this option. I am thinking that if I install a couple of cameras like these I can eventually find out where she hides. I would appreciate any suggestions about the technology and how to use it. We simply want to have the ability to find her and make sure she is home. Thanks, ---AboutFace 22 (talk) 19:50, 24 June 2016 (UTC)[reply]

If you do a web search for [cat gps tracking], you'll find that there are collars and chip implants that might be what you need (I cannot attest to effectiveness, etc.). --107.15.152.93 (talk) 20:01, 24 June 2016 (UTC)[reply]

Before we go all New World Order here, surely it is not that hard to bell a cat (if you are not a mouse, that is). Wnt (talk) 20:49, 24 June 2016 (UTC)[reply]

Domestic cats have a habit of using one site to sleep in for a few days and then choosing another site for a while. This is presumably an adaptive strategy to avoid parasite re-infection. The reason I mention this is that if you set up camera-traps, you might find where she is sleeping at the moment, but she will move on when she feels the need and your worry will return. DrChrissy ^(talk) 20:55, 24 June 2016 (UTC)[reply]

Back in the Old World Order days, I tried a bell collar. It only encouraged the cat to move more stealthily (and of course, doesn't work when cat is asleep). --107.15.152.93 (talk) 21:35, 24 June 2016 (UTC)[reply]

I'd not go for cameras, but location devices. What's your budget? This [3] bluetooth thing might work well for in-house usage, it is designed to help you find your misplaced keys and such. If you scan around the house for a minute, it should be able to help you track the cat down. There are GPS widgets for pets e.g. [4], just google for others. You don't really need GPS to establish if the cat is in the house though, and it may be of limited value on such a small scale - the cat might be in the basement or under the couch and would look the same on GPS. On the other hand, full GPS would help you find the cat even if it left the house. Finally, in my experience, this hidey-cat behavior tends to get better with age. As the cat settles in and becomes more secure, it will probably have less need to hole up out of sight. SemanticMantis (talk) 22:20, 24 June 2016 (UTC)[reply]

Another possibility is to provide her with sleeping baskets/nests - plenty of commercial ones are available. Enclosed ones are probably the best. This might increase your chances of finding her, however, if she is like my cats, she will ignore the nests and sleep in the bloody box they came in!DrChrissy ^(talk) 22:57, 24 June 2016 (UTC)[reply]

Unless the OP lives in the middle of a free-way junction where she could get run over by just stepping out side – why try and force her into being a house cat? Being house-bound is not in their nature. Also, what’s wrong with her getting lost in the house. Cats like a bit of solitude from time to time. The OP states that he is a cat person -so how about showing the cat some respect and don't treat her as an item (like a fridge, TV or Barbie Doll). She is a sentient being, like you and I -with a mind of her own. --Aspro (talk) 00:59, 25 June 2016 (UTC)[reply]
- We're supposed to be wiser, and care for our pets, who are often less wise. A cat who goes outside dies sooner than those who remain in the house. And that's a decision the human makes, not the cat. Cats are perfectly happy inside. A camera or Tile (bluetooth thing) on her collar sounds like it could help allay fears that she's gotten outside and killed without invading her space. -Nunh-huh 01:19, 25 June 2016 (UTC)[reply]

Even the smartest and strongest housecat rarely fares well against a cougar. Or a fisher. Eagles are a bit easier, but why risk the embarassment of losing her to a bird? Besides, it's not like she just wants out for an innocent stroll. If we're being empathetic here, imagine what a sentient chipmunk feels like being treated like a ball of yarn. Where's the love then? Those guys have hands, man! Plenty of animals are perfectly happy inside, and only risk the world beyond to eat, screw or crap. They indeed look at housecats with envy (and horror), not pity. InedibleHulk (talk) 04:06, 25 June 2016 (UTC)[reply]

Thank you very much for the multitude of suggestions. Yes, we want her to be an indoor cat but we live in a house with large windows and the cat begins to mew in the morning asking us to open the windows and doors for her. She understands what the freedom means. That's why we are so scared. Every time she disappears for 10 hours we think she's escaped. Yes, my wife will pay any money to be able to monitor her. We actually flew her from Europe with an escort when my brother died, she was his cat. Thanks --AboutFace 22 (talk) 02:47, 25 June 2016 (UTC)[reply]

Well, you've got more of a wife problem than a cat problem. I'm not being nasty, and in fact I sympathise with her, but cats are gonna do what cats want to do.http://pettrackingoz.com.au/products/petrek-lt-905g is the sort of gizmo I'd have liked for my most recent cat, who was easily capable of sleeping in any random spot for 12 hours at a time. Don't fret about the cat running away, unless someone offers her a better option she'll be back when she's hungry or bored. Greglocock (talk) 03:39, 25 June 2016 (UTC)[reply]

So the cat grew up in Europe and now no longer lives there? I don't know about your cat specifically, but most cats in Europe are free to go outside. She may be used to it. But maybe the outside world is more dangerous where she lives now than it was in Europe. PiusImpavidus (talk) 09:03, 25 June 2016 (UTC)[reply]

Cats are gods, it is both futile and sacrilege for their human servants to want to know too much about their nocturnal perambulations and other ritual activities. Your cat has chosen you to be its slave, it may not be challenged. Roger (Dodger67) (talk) 10:43, 25 June 2016 (UTC)[reply]

Couldn't agree more with Roger. Cats have needs. Just like Maslow's hierarchy of needs. Food, shelter and warmth are not enough. “Research shows that when people live lives that are different from their true nature and capabilities, they are less likely to be happy than those whose goals and lives match.”; same for cats – let her have a life. Then she will always return home to those that provide those right basic needs. 6 Pets that Traveled Long Distances to Get Home. You could instill in her paranoia by tracking her so that your always know where she is. This over-protection that your wife strive for, drives some teenagers to leave home and brake all contact with their parents. They become missing persons.--Aspro (talk) 15:13, 25 June 2016 (UTC)[reply]

People should be left alone too make their own decision on indoor vs. outdoor cats. They really don't need advice or opinions. Far better to talk about something that nobody has a strong opinion about, like the 2016 US presidential election, climate change, abortion, or gun control. :( --Guy Macon (talk) 16:49, 25 June 2016 (UTC)[reply]

The OP is asking for opinions though - in order to be better and more responsible cat owners to a cat that they cherish and feel fond of– and the majority consensus here, is that his wife is unwittingly standing on the wrong premise and so thwarting the cat's natural instincts. Relax – let the cat be a cat and stop trolling. --Aspro (talk) 17:39, 25 June 2016 (UTC)[reply]

Cats, cats and more cats. Meow is the time! InedibleHulk (talk) 00:59, 27 June 2016 (UTC)[reply]

Comment Readers of this thread may also be interested to read another thread about introducing a cat to a new home. Wikipedia:Reference desk/Archives/Science/2016 May 18#Cat in a new home DrChrissy ^(talk) 15:45, 25 June 2016 (UTC)[reply]

@DrChrissy, I am familiar with the post you are pointing to. It actually inspired my post here. It is amazing how many emotions the cats induce in us. That post especially, my daughter's advice to keep the cat indoors for her own good and longevity, as well and some observations in our neighbourhood which is partly rural have cemented our determination to keep our treasured animal indoors. I walk around on the weekends and see domestic outdoor cats roaming around and then you see a post somewhere, cat lost. We have coyotes, hawks, etc. She is a little animal. Still her attempts to get out after looking outside through our large glass panels is heartbreaking. It is mew after mew. We are in the United States but this cat in the old country was an indoor cat and she lived on the eighth floor of an apartment building. I really appreciate all opinions. Thank you --AboutFace 22 (talk) 18:06, 25 June 2016 (UTC)[reply]

Thanks for this. In my real life, I work on the science of animal welfare, particularly captive animals. A lot of discussion on animal welfare is about frustration of their motivations. However, we must not be anthropocentric about this. We do not have the same senses and motivations as cats. We are "locked in our own skin". Do you really know that she is mewing to get outside? When my cats see a bird through the window, they stay where they are and "chatter" at them through the glass, choosing not to go through my propped-open door which is only 3 metres away to chase them. Keeping your cat indoors to prevent her from being predated is certainly improving your cat's well-being, but animal welfare is widely considered these days to be about the animal's feelings. If your cat is not getting frustrated at being unable to get out, all is well. However, if your cat is frustrated, this could be having a negative effect on her welfare (please do not take this as an accusation whatsoever of wrong-doing on your part - I am simply putting forward an academic argument). DrChrissy ^(talk) 19:59, 25 June 2016 (UTC)[reply]