Recent comments in /f/askscience

brandude87 t1_j4tsvs8 wrote

Reply to What happens to the energy of sound in space? by full_hammer

If you still had air in your lungs and yelled directly into someone else's ear with your dying breath, it may still be audible to the other person. However, your mouth must completely encapsulate the other person's ear to prevent the air gases from instantly vaporizing into tiny liquid droplets and ice crystals. Furthermore, the air bubble exhaled from your mouth into their ear will be traveling far slower than the speed of sound, so the sound waves will have bounced around the bubble quite a bit before reaching their eardrum, causing your yell to sound muffled, but possibly still intelligible.

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MJBrune t1_j4tsnvf wrote

Reply to It seems like the effective dosage of most medications tend to be in the 5mg to 200mg range (although there are some medications with smaller or larger dosages). Is this an accurate observation? If so, why? by Fbg2525

Average human size really is what it comes down to. Only so many mgs got in your blood. Only so many receptors for those chemicals. That said the range you have is far under what I typically see for ibuprofen or Tylenol. Which is in the 400 to 600 range. So you might have some observational bias in there too.

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horsetuna t1_j4ts8uz wrote

Reply to Extinction of the Dinosaurs: What did I miss? by cakedayCountdown

I don't know much about why they thought the peninsula formed. The current crater from the chixulub impact is half under the land and half under the sea, and does not seem to follow the coastline as it is today.

Mostly what convinced people was the timing and size. Before the Alvarez team (father and son) found the iridium in the KT boundary, there wasn't any evidence that there was a meteoric strike at the right time of the right size. After they found the iridium, they looked for other records from mining/gas companies, as people wanted the smoking gun .. the crater itself.

They calculated how big a bolide would be needed to coat the earth in such a way with this amount of iridium and then calculated the size of the crater, as well as the age.

The crater had actually been known for a while but the company that did the surveys wasn't keen on sharing their info due to competition concerns (not specifically about the crater iirc)

Finally once the crater was found, dated and confirmed it was accepted more or less. Better climate modelling showing the extent of the conditions also helped the case

Many think it wasn't the ONLY factor though. But a contributing one. The last straw that broke the camels back so to speak.

For instance the Deccan traps in India is the remains of a massive flood basalt that occured around the same time and likely contributed to the situation with the bolide (some claim the impact caused the volcanic eruption, the shock waves converging on the far side of the planet where India would have been at the time. But less evidence for that).

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EmperorGeek t1_j4trkjz wrote

Reply to How does lightning illuminate the sky? by AverageMan282

Lightning doesn’t tend to occur in clear skies. There are usually plenty of clouds to reflect the light of the bolt. Clouds being made of small droplets of water, so your assumption of refraction/reflection by water is accurate.

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