It's Flowey.
Also, the shape of the Earth is not a human standard while the begining of the degrees in cartography is.
How to navigate on a planet with the SRV
- Thread starter kilon
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It's Flowey.
Also, the shape of the Earth is not a human standard while the begining of the degrees in cartography is.
Well done. The world has become a bit dumber again.
It is, however, approximated by human standards. We apply geoids to it, to be able to fit reference coordinate systems better. Of course, the Earth changes shape all the time, so the geoid has to be updated from time to time.
Here is a bit of light reading about it: https://oceanservice.noaa.gov/facts/geoid.html.
Enjoy!
S
So is the author of "College Physics" a flat earther or a creationist?
As I said, physics/math use a different standard than cartography.
Actually not quite correct. There are, as has been stated, different ways to record location. And surveyors and cartographers use different ones depending on the scale looked at.
The basic problem is that the earth approximates a sphere, so on large scales, to preserve angles, geographical coordinates work best.
On smaller scales, projected coordinates work quite well, as the surface of the earth approximates a flat surface. Then it is simple to overlay a simple grid similar to the one in your image, and record the position as X (easting) and Y (northing). Any movement to the east in such system would be written as (x + n, y), and any movement to the north would be (x, y + n).
Typically, on nation and continent scale you are best off using degrees. But for actual surveying on smaller scale, a projected grid is easy to manage. The physics example can get away with it, as the scale is relatively small and the planes position relative to earth is not important.
You can probably recalculate the whole thing with geographical coordinates in relation to the centre of the earth. If you want to.
SActually not quite correct. There are, as has been stated, different ways to record location. And surveyors and cartographers use different ones depending on the scale looked at.
The basic problem is that the earth approximates a sphere, so on large scales, to preserve angles, geographical coordinates work best.
On smaller scales, projected coordinates work quite well, as the surface of the earth approximates a flat surface. Then it is simple to overlay a simple grid similar to the one in your image, and record the position as X (easting) and Y (northing). Any movement to the east in such system would be written as (x + n, y), and any movement to the north would be (x, y + n).
Typically, on nation and continent scale you are best off using degrees. But for actual surveying on smaller scale, a projected grid is easy to manage. The physics example can get away with it, as the scale is relatively small and the planes position relative to earth is not important.
You can probably recalculate the whole thing with geographical coordinates in relation to the centre of the earth. If you want to.
I'm aware that the sphere is locally euclidean though my guess would be that for the rest of the Earth it's worth using differential geometry which is beyond me (currently). Still, establishing north as 0º doesn't evade the geometry of the Earth either.
Yes, it is just convention. Equator is 0° latitude, Greenwich is ° longitude. The compass rose is orientated so a north bearing is towards 0°. A nice starting point for navigating a sphere. In your example, the angles are deviations from the heading of the plane, however, which just happens to be due north.
SI'd just like to say that it is awesome to come to a game forum and read up on relationships and differences between maps (flat) and globes (spherical). Although having been aware of the problem, I never thought to learn about it before!
And in reply to this
Who is the dumb one? He who talks about their understandings and so gets explanations, or he who snipes from the sideline and shows their poor attitude?
And in reply to this
Who is the dumb one? He who talks about their understandings and so gets explanations, or he who snipes from the sideline and shows their poor attitude?
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Hear hear. Sorry I forget but have you been following straha's circumnavigation? There's some beautiful stuff to be learned in there too!
https://forums.frontier.co.uk/showthread.php/444913-Meridian-a-planetary-circumnavigation
Yes. I'm following all 3 circumnavigation threads!
Robert Maynard
Volunteer Moderator
When I was writing the surface navigation portion of StatusDisplay, I found this to be a good source of the relevant formulae: http://www.edwilliams.org/avform.htm
Yes, it is just convention. Equator is 0° latitude, Greenwich is ° longitude. The compass rose is orientated so a north bearing is towards 0°. A nice starting point for navigating a sphere. In your example, the angles are deviations from the heading of the plane, however, which just happens to be due north.
It is not a coincidence: "Calculate the wind velocity for the situation shown in Figure 3.48. The plane is known to be moving at 45.0 m/s due northrelative to the air mass, while its velocity relative to the ground (its total velocity) is 38.0 m/s in a direction 20.0º west ofnorth."
You must transform such indications into an angle to calculate the direction & for that you take the East as 0º, it also could be said that it is deviating from any cardinal direction but my point stands, physics/math don't use the same standard as cartography.
Sorry Flowey, but you're taking East as 0º because that's the convention that's being set out in the book for the problem. You don't have to use East as 0º.
Here's a problem from another Physics book:
As you can see for this problem, the angle is being measured relative to North.
Now you could convert the problem to measure the angles relative to East, but it would be a pointless* endeavour as all you would be doing would be adding more steps to get the same result. (*unless the point of the exercise is co-ordinate transformation, of course.)
Really, the standard (if there can be said to be one) in Physics/Maths is to use the co-ordinate system which is most appropriate to the problem.
Avago Earo
Banned
I don't know what physics is being taught here. If we look at a circle starting at the top (N), we would be at 0. Counting clockwise until we are at 90 degrees we will arrive at (E), a further 90 degrees (180 from (N)) and we are (S), moving another 90 degrees (270 from (N)) and we are at (W)), another 90 degrees (360 from (N)) and we are back at 0. We have gone full circle.
Maybe your Physics teacher is using Mecca as a reference point.
Now that makes me wonder, wouldn't the same be true about cartography?
It's not even the teacher, it's the way it's taught in a college book & actually I know realize that the direction of the angle is also inverted as in math & physics angles are counted counter-clockwise.
We all got the cake.
It would only be true if the application was unimportant. I guess in simplest terms, if I hand you a sheet of paper and say "Draw a 46° angle from this line segment" it really doesn't matter the orientation, but if I hand you a map and ask "What towns are along a heading of 46° from this town?" then yeah, the standard is crucial.
I would say so, yes.
To take a pertinent example, for a galactic map, using the Earth's North-South polar line as North-South for the galaxy map would not work well, and using any Map/Compass direction would be even worse, as the tangential vector constantly changes relative to the galaxy dependent on both time ans position on the Earth. So it would be much more practical to define and use a galactic North-South and East-West are used instead.
UK Ordnance Survey maps use grid references - see https://getoutside.ordnancesurvey.co.uk/guides/beginners-guide-to-grid-references/
You might also define a map using landmarks rather than compass direction but that would generally be for very specific purposes.
There's also lots of different ways to project the Earths curved surface onto a flat map, and different ones are better for different purposes.
In general though it would make sense to use commonly recognised standards unless there was a good reason to do otherwise.
Edit - just an additional point in case you're not aware of it - the position of magnetic North (i.e. the direction pointed by a compass) changes, so maps use a different North, and when navigating via compass you need to adjust for the current position of magnetic North relative to grid/map North.
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