by alter-ego » Mon Dec 06, 2021 3:48 am
neufer wrote: ↑Mon Dec 06, 2021 2:01 am
alter-ego wrote: ↑Mon Dec 06, 2021 1:52 am
Chris Peterson wrote: ↑Sun Dec 05, 2021 10:58 pm
Of course, depending on whether you learn about this in an electronics class or a physics class determines whether you view the relationship between "current flow" and "particle movement" as being the right or the wrong way!
I'm not sure why electromagnetics was brought into this. A more direct basis for the right-hand rule is within
rotational kinematics that defines the angular momentum vector.
It's all agreed upon convention...NOT BASIC PHYSICS...
(like the definition of the magnetic B/H field direction.)
The most common double helical structure found in nature (i.e., B-DNA) is right-handed and all antineutrinos are right-handed. However, globes have Antarctica at the bottom because few people live there (or anywhere near there) and:
- 1) For most people & major civilizations: the North Star is "up"
2) and most people are both right-handed & right-footed
https://en.wikipedia.org/wiki/Handedness wrote:
<<In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or better in dexterity. The other hand, comparatively often the weaker, less dextrous or simply less subjectively preferred, is called the non-dominant hand. Right-handedness is by far more common; about 90% of the human population are right hand dominant.
Left-handed people are more likely to have several specific physical and mental disorders and health problems. As handedness is a highly heritable trait associated with various medical conditions, and because many of these conditions could have presented a Darwinian fitness challenge in ancestral populations, this indicates left-handedness may have previously been rarer than it currently is, due to natural selection.>>
A legacy origin predating any consideration of physics is the only answer. I fell prey to the convenient coincidence, and an apparent setup
Maps have ‘north’ at the top, but it could’ve been different wrote:
...
It is only within the last few hundred years that north has been consistently at the top
...
Given that each culture has a very different idea of who, or what, they should look up to it’s perhaps not surprising that there is very little consistency in which way early maps pointed. In ancient Egyptian times the top of the world was east, the position of sunrise. Early Islamic maps favoured south at the top because most of the early Muslim cultures were north of Mecca, so they imagined looking up (south) towards it. Christian maps from the same era (called Mappa Mundi) put east at the top, towards the Garden of Eden and with Jerusalem in the centre.
So when did everyone get together and decide that north was the top?
It’s tempting to put it down to European explorers like Christopher Columbus and Ferdinand Megellan, who were navigating by the North Star. But Brotton argues that these early explorers didn’t think of the world like that at all. “When Columbus describes the world it is in accordance with east being at the top,” he says. “Columbus says he is going towards paradise, so his mentality is from a medieval mappa mundi.”
We’ve got to remember, adds Brotton, that at the time, “no one knows what they are doing and where they are going”.
Mercator’s world map, from 1569, was almost certainly a defining moment in north-up map-making. His map was famously the first to take into account the curvature of the Earth, so that sailors could cross long distances without overshooting the mark.
...
So, the answer to the question of which way up is the Earth is simple: it is not any particular way up and there is no good reason other than a historical superiority complex to think of north as being the top of the world.
...
Specifically, within the discipline of astronomy, it's possible that a world-wide committee of astronomers
could agree to define an official "up" direction that could align right-hand rule to the coincidental north-up view. (Similarly, Pluto was "demoted" to a dwarf planet by a collective agreement). However, the only reason to define an 'up' direction is to officially formalize a standard, but I don't think this would ever make it to that level of importance.
[quote=neufer post_id=318802 time=1638756114 user_id=124483]
[quote=alter-ego post_id=318800 time=1638755553 user_id=125299]
[quote="Chris Peterson" post_id=318792 time=1638745127 user_id=117706]
Of course, depending on whether you learn about this in an electronics class or a physics class determines whether you view the relationship between "current flow" and "particle movement" as being the right or the wrong way!
[/quote]
I'm not sure why electromagnetics was brought into this. A more direct basis for the right-hand rule is within [url=https://courses.lumenlearning.com/boundless-physics/chapter/vector-nature-of-rotational-kinematics/]rotational kinematics[/url] that defines the angular momentum vector.[/quote]
[c][b][color=#0000FF]It's all agreed upon convention[/color]...[u][color=#FF0000]NOT BASIC PHYSICS[/color][/u]...[/b]
(like the definition of the magnetic B/H field [b][u]direction[/u][/b].)[/c]
The most common double helical structure found in nature (i.e., B-DNA) is right-handed and all antineutrinos are right-handed. However, globes have Antarctica at the bottom because few people live there (or anywhere near there) and:
[list=]1) For most people & major civilizations: the North Star is "up"
2) and most people are both right-handed & [url=
https://en.wikipedia.org/wiki/Footedness]right-footed[/url][/list]
[quote=https://en.wikipedia.org/wiki/Handedness]
<<In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or better in dexterity. The other hand, comparatively often the weaker, less dextrous or simply less subjectively preferred, is called the non-dominant hand. Right-handedness is by far more common; about 90% of the human population are right hand dominant.
Left-handed people are more likely to have several specific physical and mental disorders and health problems. As handedness is a highly heritable trait associated with various medical conditions, and because many of these conditions could have presented a Darwinian fitness challenge in ancestral populations, this indicates left-handedness may have previously been rarer than it currently is, due to natural selection.>>[/quote]
[/quote]
[hr][/hr]
[hr][/hr]
A legacy origin predating any consideration of physics is the only answer. I fell prey to the convenient coincidence, and an apparent setup :lol2:
[quote="[url=https://www.bbc.com/future/article/20160614-maps-have-north-at-the-top-but-it-couldve-been-different]Maps have ‘north’ at the top, but it could’ve been different[/url]"]
...
[i][size=110]It is only within the last few hundred years that north has been consistently at the top[/size][/i]
...
Given that each culture has a very different idea of who, or what, they should look up to it’s perhaps not surprising that there is very little consistency in which way early maps pointed. In ancient Egyptian times the top of the world was east, the position of sunrise. Early Islamic maps favoured south at the top because most of the early Muslim cultures were north of Mecca, so they imagined looking up (south) towards it. Christian maps from the same era (called Mappa Mundi) put east at the top, towards the Garden of Eden and with Jerusalem in the centre.
So when did everyone get together and decide that north was the top? [b][color=#0000FF]It’s tempting to put it down to European explorers like Christopher Columbus and Ferdinand Megellan, who were navigating by the North Star.[/color][/b] But Brotton argues that these early explorers didn’t think of the world like that at all. “When Columbus describes the world it is in accordance with east being at the top,” he says. “Columbus says he is going towards paradise, so his mentality is from a medieval mappa mundi.” [b][color=#0000FF]We’ve got to remember, adds Brotton, that at the time, “no one knows what they are doing and where they are going”[/color].[/b]
[size=110][color=#FF0000]Mercator’s world map, from 1569, was almost certainly a defining moment in north-up map-making.[/color][/size] His map was famously the first to take into account the curvature of the Earth, so that sailors could cross long distances without overshooting the mark.
...
So, the answer to the question of which way up is the Earth is simple: it is not any particular way up and there is no good reason other than a historical superiority complex to think of north as being the top of the world.
...[/quote]
Specifically, within the discipline of astronomy, it's possible that a world-wide committee of astronomers [i]could[/i] agree to define an official "up" direction that could align right-hand rule to the coincidental north-up view. (Similarly, Pluto was "demoted" to a dwarf planet by a collective agreement). However, the only reason to define an 'up' direction is to officially formalize a standard, but I don't think this would ever make it to that level of importance.