Wikipedia:Reference desk/Archives/Science/2024 September 2

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September 2

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Is the nose of a grizzly or a brown bear cold?

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Do bears have a cold nose like a dog? Wasn't able to find an answer with Google and finding out myself would be against the policies of my health insurance. --Question123Ka (talk) 04:46, 2 September 2024 (UTC)[reply]

Dog noses are cold because they are cooled by the evaporation of moisture on their noses. Dog noses are moist because dogs lick their noses when they get dry. So the question amounts to, do bears lick their noses, regularly? I suppose your health insurance covers the risks of an investigation if carried out in a zoo or using binoculars or a zoom lens.  --Lambiam 06:29, 3 September 2024 (UTC)[reply]
I don't go outside. That's where bears live.
But thanks, you helped me: If one specifically searches for bear and wet nose or rhinarium, one might find some results. At least one in Google Books: International Wildlife Encyclopedia, where they say brown bears have a wet nose.
Google as such is so dead, however. Just stock photo spam and ads for sweatshop products. --Question123Ka (talk) 12:32, 3 September 2024 (UTC)[reply]
 
This polar bear's nose is at about 15°C, but I can't find a thermogram of a brown bear.  Card Zero  (talk) 08:40, 3 September 2024 (UTC)[reply]
Thanks, that's exactly what I found out too, that polar bears have a cold nose (means: colder than the rest of their body). I'm mostly interested how it would feel to touch a bear's nose. --Question123Ka (talk) 12:32, 3 September 2024 (UTC)[reply]
According to the book "Grizzly Bear Science and the Art of a Wilderness Life," all bears lose heat primarily through their paws, but also through area with limited hair such as their nose and ears. That makes the nose appear warmer than the surroounding face because it is radiating more heat. Checking "Ecology and Behaviour of North American Black Bears," it agrees that all bears lose heat through their paws, ears, and nose. It also states that the grizzy and black bears have a stronger sense of smell compared to other bears and they further accentuate it by using their tongue to force air into their nose in a motion that looks like licking. A side effect of this is that the water evaporates on their wet nose, cooling it down, and allowing more heat to escape. As a result, grizzly and black bears tend to have more and larger blood vessels just under the surface of their nose. Being so close to the Appalacians, we have plenty of books on bears, but most are aimed towards children. I didn't check those because I assume they won't have anything of interest and, usually, they don't have an index where I can quickly look for pages about the bear's nose. 75.136.148.8 (talk) 10:44, 5 September 2024 (UTC)[reply]

Quote from the article: "A potential efficiency loss of only 12.79% can be achieved, or 4.26 kW⋅h/kg out of 33.3 kW⋅h/kg." What is the reason for using 4.26 out of 33.3? Is there some significance to those numbers? I get 12.79 out of 100 but what is special about 4.26 out of 33.3? 196.50.199.218 (talk) 13:49, 2 September 2024 (UTC)[reply]

The section was introduced in this edit, you could try to contact the author (but they haven't edited since 2018). I cannot find those numbers in the reference given. Not sure what to make of that. --Wrongfilter (talk) 14:36, 2 September 2024 (UTC)[reply]
Hydrogen energy density which is 120mj/kg is 33.3kwh. 156.155.127.55 (talk) 15:05, 2 September 2024 (UTC)[reply]