Questions in the Science & Nature category.
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June 28

Mathfilter - Surface of a Helix

My math is a bit rusty, I would like to calculate the surface of a helix [more inside]
posted by yoyo_nyc at 4:15 AM - 3 answers

June 24

Another what's-that-bird question

What's this goose-like bird I saw in Oakland, CA this evening? [more inside]
posted by crazy with stars at 8:33 PM - 7 answers

June 23

What do you suppose caused this?

Submitted for your consideration: Two photographs of the same place- in 1974 and 2014. [more inside]
posted by pjern at 2:30 AM - 8 answers

June 21

Failed kiddie chemistry experiment

We tried to do the Iodine Clock Reaction today for the kids, using 1) HSO3 mixed with starch and 2) KIO3. Unfortunately, instead of changing from colourless to dark blue (cue impressed sounds from the kids) there was no colour change at all. No precipitate or apparent temperature change, either, so I'm not sure anything at all happened chemically. Any ideas what might have gone wrong?
posted by thelaze at 6:06 PM - 7 answers

ADHD and working memory

Can working memory impairment be reliably inferred from a diagnosis of ADHD? How often do individuals meet the diagnostic criteria for ADHD without showing substantial impairment on measures of WM? Is it appreciably often the case that WM memory deficits in childhood and early adolesence are resolved during the process of maturation?
posted by anonymous at 6:45 AM - 1 answers

June 20

Birders or Ornithologists: Explain this bird in flight photo

What happened just before and after this 1/4000th of a second of a swift's flight? Birds aren't planes so my guess of rapid clockwise rotation is probably wrong. Many swifts were feeding. Some would dive, level out along this wall then abruptly turn away. I'm not sure they were swifts, but other photos show the forked tail. Photo taken in Fes, Morocco.
posted by Homer42 at 5:23 AM - 4 answers

June 19

What is this piece of chemistry glassware for?

What on earth is this item of chemistry glassware for?
posted by BuddhaInABucket at 8:27 PM - 4 answers

June 17

Why the seltzer always explodes?

Why does seltzer explode on the regular but flavored sodas rarely do under the same conditions? [more inside]
posted by atomicstone at 4:32 PM - 5 answers

June 14

is this a bed bug?

I found two of these guys crawling on me during a 2 night hotel stay, but couldnt find any more in the bed, or any other evidence of bedbugs, no bites that i can find.. What do you think? http://imgur.com/a/d0KUP
posted by PercussivePaul at 2:04 PM - 9 answers

June 12

(Bed?)Bug ID

Please help me understand if this is a bedbug. [more inside]
posted by anonymous at 3:20 PM - 10 answers

How much fossil fuel do I use to walk a mile?

It takes 10 kilocalories of fossil-fuel to make 1kcal of food. You use 80kcal to walk a mile. There are 31520kcal per gallon of gasoline. 80kcal * 10 = 800kcal of fossil-fuel per walking-miles. 31520kcal/800kcal=39.4 walking-miles/gallon of gas? What am I missing? Can I trust the 10:1 fossil:food ratio?
posted by gregr at 8:39 AM - 14 answers

June 11

Surly Birds: Ugly Pigeon, or Juvenile Griffin? Can You ID This Bird?

Walking through historic Chestertown, Maryland, last week, and saw this Hellspawn bird sitting on someone's front porch. Staring... [more inside]
posted by It's Raining Florence Henderson at 5:15 PM - 9 answers

Does anyone here have experience growing crystals?

What types of crystals should I look into growing if I want them to grow/attach onto a wooden panel? [more inside]
posted by modernsquid at 5:06 PM - 11 answers

Changing instruments in social research - values vs validity

I am looking for articles, case studies and examples in which researchers in the social sciences change (or consider changing, or are called on to change) research instruments (questionnaires, rating scales, assessment measures) to accommodate changes in social values. Specifically, I am interested in the discourse and debate around these changes, and the ways in which researchers attempt to manage the inherent statistical risks to internal validity instrument change entails. What should I read? [more inside]
posted by embrangled at 2:51 AM - 3 answers

June 10

what plant is this?

What plant is this?
posted by tarvuz at 3:46 AM - 4 answers

June 9

What Bird Is This?

I've heard this bird ever since childhood, but have never been able to identify it. [more inside]
posted by Jangatroo at 11:51 AM - 8 answers

June 8

Tiny bugs crawling out of my Macbook

In the last two days I've noticed about a dozen tiny, almost microscopic bugs crawling around, into and out of my Macbook Air keys. I'm freaking out, not only because I'm worried they're going to destroy the laptop but because this could potentially be a bigger problem in the house. [more inside]
posted by rbf1138 at 3:18 PM - 10 answers

June 7

What kind of tree is this?

Need help identifying a tree from Utah. [more inside]
posted by _DB_ at 8:12 PM - 5 answers

June 4

Spontaneous creation out of nothing

I have a physics question, but my googling hasn't been able to provide anything satisfactory tonight. It's about cosmological models of creation in which NO initial conditions whatsoever are assumed. [more inside]
posted by naju at 7:12 PM - 14 answers

What are these geological features?

What are these geological features? [more inside]
posted by odinsdream at 11:25 AM - 6 answers

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