Wikipedia:Reference desk/Archives/Science/2021 January 31

= January 31 =

Which theory explains Earth rotation?
If Einstein's General relativity explains Earth revolution, then which theory explains Earth rotation? Rizosome (talk) 06:34, 31 January 2021 (UTC)
 * Are you asking why the earth spins? ←Baseball Bugs What's up, Doc? carrots→ 08:03, 31 January 2021 (UTC)


 * Courtesy link: Earth's rotation, specifically Earth's rotation.
 * Please clarify the premise of your question. Are you highlighting some aspect of the Earth's revolution which is inadequately described by Newtonian physics?
 * Note: It is best to use internal wikilinks (double square brackets) when linking Wikipedia articles. If you wish text other than the article name to appear in a link, then use piped links (see WP:PIPE), such as " Earth revolution " which yields Earth revolution.
 * -- ToE 14:02, 31 January 2021 (UTC)

What makes Earth spin? Rizosome (talk) 14:14, 31 January 2021 (UTC)
 * Love Makes the World Go 'Round —2603:6081:1C00:1187:3439:5742:B1FB:BCCC (talk) ~ — Preceding undated comment added 16:03, 31 January 2021 (UTC)


 * Spin is ubiquitous in the cosmos. Planets rotate, as do stars and galaxies. This comes about simply from conservation of angular momentum. When two ice skaters (or celestial bodies) approach each other and link arms (or are attracted due to gravity), they will start rotating.--Shantavira|feed me 16:24, 31 January 2021 (UTC)


 * Unfortunately, the angular momentum Wikipedia article is rather technically dense, and by the second paragraph is already introducing terminology likely to confuse the average layperson. This video from the YouTube channel "Science Asylum" does a pretty good job explaining the role of angular momentum in the formation of the solar system.  This video from Universe Today deals with the same issue as well.  -- Jayron 32 14:50, 1 February 2021 (UTC)

Into what does the human body convert acetic acid?
The human body normally converts ethanol to acetaldehyde which is more poisonous. Then acetaldehyde to acetic acid (vinegar) which is less poisonous than ethanol. But what does it convert the acetic acid into? JRSpriggs (talk) 22:20, 31 January 2021 (UTC)
 * WHAAOE. It's metabolised to acetyl-CoA: see Ethanol metabolism, which also explains what happens next. {The poster formerly known as 87.81.230.195} 90.200.40.9 (talk) 02:48, 1 February 2021 (UTC)
 * Yep, this is how it can be "burned" for energy as a macronutrient. Acetyl-CoA is the "entry point" into the citric acid cycle for nutrients. The all-ethanol diet is not recommended, however. --47.152.93.24 (talk) 17:31, 1 February 2021 (UTC)