Difference between revisions of "Talk:2520: Symbols"

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(Add note about the "real part" operator)
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: Could be the remainder of a series (i.e. the error when using the first terms of the series as an approximation). Determining upper bounds on this error is usually very tedious.
 
: Could be the remainder of a series (i.e. the error when using the first terms of the series as an approximation). Determining upper bounds on this error is usually very tedious.
 
: R sub e is tire effective rolling radius (or effective radius)--a radius based on the distance traveled by one rotation of a pneumatic tire.  Re is similar to the unloaded radius (for radial tires) and normally larger than the loaded radius (distance from axle to ground).
 
: R sub e is tire effective rolling radius (or effective radius)--a radius based on the distance traveled by one rotation of a pneumatic tire.  Re is similar to the unloaded radius (for radial tires) and normally larger than the loaded radius (distance from axle to ground).
 +
: My first thought was that this referred to the "real part" operator, although that's typically represented by a plain Re (no subscript).
  
 
T to the fourth power looks like blackbody radiation, any ideas what specifically that formula represents? [[Special:Contributions/162.158.203.22|162.158.203.22]] 20:40, 24 September 2021 (UTC)
 
T to the fourth power looks like blackbody radiation, any ideas what specifically that formula represents? [[Special:Contributions/162.158.203.22|162.158.203.22]] 20:40, 24 September 2021 (UTC)

Revision as of 01:40, 26 September 2021


Great work by whomever did this, but is it possible R_e is something else? I agree that the numerical aspect makes it seem like a fluid mechanics problem, but I've never seen the Reynolds number with a subscripted e... only a regular size e, such that it is Re, not R_e. 108.162.237.93 20:36, 24 September 2021 (UTC)

R sub e (not Re) is Effective Reproduction Number. This is related to infection rates. I'm pretty sure it's R sub e, not Re given that infection rates are very much on his mind right now.
It would be out of place relative to all the other entries, though, which are all physics related. IMO it's more likely this was an error.
Earth's radius is abbreviated "R sub e" 162.158.107.4 21:30, 24 September 2021 (UTC)
Could be the remainder of a series (i.e. the error when using the first terms of the series as an approximation). Determining upper bounds on this error is usually very tedious.
R sub e is tire effective rolling radius (or effective radius)--a radius based on the distance traveled by one rotation of a pneumatic tire. Re is similar to the unloaded radius (for radial tires) and normally larger than the loaded radius (distance from axle to ground).
My first thought was that this referred to the "real part" operator, although that's typically represented by a plain Re (no subscript).

T to the fourth power looks like blackbody radiation, any ideas what specifically that formula represents? 162.158.203.22 20:40, 24 September 2021 (UTC)

There's an equation for what reflects off a spherical object that is a quartic equation (although I'd expect concave reflectors, not convex ones, to risk skin-burn. Or, more likely something to do with UV (non-)absorbtion or generation, but I imagine someone knows exactly what it is, without someone like me just guessing wildly. ;) 141.101.99.82 21:05, 24 September 2021 (UTC)

This wiki does not seem to have a consistent formatting structure for lists

The NA could also soon become NAN (not a number) thus being only a step away from the dangerous arthmeric error. --162.158.88.43 21:38, 24 September 2021 (UTC)

Bold Title

Content starting with a tab


  • Bold title content continues on same line


  • Regular title

Content on a new line, but not starting with a tab

As well as tables and mixes of these formats. Maybe someone should pick one and apply it to all the explanations. I just noticed it because of the inconsistencies as people are quickly throwing something together for this new comic. 162.158.107.4 21:02, 24 September 2021 (UTC)

I read the penultimate line as "Mg" and was trying to imagine a meaning for "megagrams per kilogram". Sloppy Greek letter there, Randall. Nitpicking (talk) 03:17, 25 September 2021 (UTC)

Why are partial derivatives considered graduate-level? They're typically covered in first level undergraduate science courses, along with gradients and such. FPSCanarussia (talk) 03:34, 25 September 2021 (UTC)

The reference to "micrometer" links to the Wikipedia page for the measuring device, but it should link to the page for the unit of length: https://en.wikipedia.org/wiki/Micrometre Professor Frink (talk) 15:58, 25 September 2021 (UTC)

Adding to “Micrometer/Micrometre” above: this “any” is not really correct:

Of course, micrometers are used as a measurement of distance in other contexts, but any distance-measuring device capable of accurately measuring micrometer distances would also be expensive.

The “Micrometers” as seen in the Wikipedia article can measure distances of some micrometers accurately, but are not really expensive. Probably even cheaper than any equipment which can not measure distances. --162.158.88.239 18:19, 25 September 2021 (UTC)

In certain circles (or, perhaps, between them as they roll), the typical Reynolds number is just three digits... ;) 162.158.159.95 20:04, 25 September 2021 (UTC)

"When radiative transfer is large enough to be the most important form of heat interchange, it is normally also large enough to sear the skin with thermal or ultraviolet burns." Radiative transfer is the dominant heat transfer from a (idle) human body in a 20C room. There is no risk of seared skin in this situation. As an aside if people understood the role of radiative heat transfer we'd have more comfortable and cheaper HVAC systems (and more underfloor heating).172.70.34.91 20:08, 25 September 2021 (UTC)

I cannot recall ever using Avogadro's constant in a stochiometric calculation. You do everything in mole or gram mole. NA implicitly cancels and never even appears.172.70.34.91 20:08, 25 September 2021 (UTC)