#coordinate systems

-- Cartesian System = used for linear motion

-- Polar System = used for angles

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"Hi! It might be a dumb question but it's been in my mind for a while. We are convinced that North is up and South is down because that's the way maps have been for many many years, but we don't really know which way is actually up, it could be east or northwest, etc, right? Because there isn't a real orientation/position in space, there's no fixed up or down, but... doesn't the way the Earth rotate determine in a way which way is up? How do those two things related to each other? Or is there no connection at all? Thank you!"

You’re right that the way we draw our maps with North pointing up and South pointing down is largely arbitrary, and indeed there are a number of maps with the Southerly direction at the top rather than at the bottom, and they’re good fun to look at.  However, there are good reasons to say that a Northerly or Southerly direction should be “up”, and these reasons extend beyond just the rotation of the Earth.

The rotation of the Earth is a good starting place, though - the rotation axis of the Earth goes more or less through the North and South magnetic poles of the Earth. The magnetic North & South poles wander a little, so some years they’re closer to the rotation axis than others. Fixing the rotation of the Earth as a cardinal direction makes good sense, and is what we’ve done - East and West point 90 degrees from North and South.

There’s one more reason to put North as up, and it’s a physics convention. Most of the time, when we’re talking about rotation, we say that the direction of the rotation axis is actually just in one direction, rather than having to indicate both North and South. If we do this, it allows us to encode both the axis of rotation, and the direction of rotation at the same time. The way we determine which of North or South should be “the direction”, we use what’s called the “right hand rule”. You curl your fingers in the direction of rotation, and your thumb points in the direction of the rotation axis. In the Earth’s case, we rotate towards the East, so your thumb will point in the direction of North.

However, if you’re thinking of orientations beyond just the Earth’s own rotation, while it’s true that there’s no way to set an entirely objective zero point from which to measure other positions, and a sphere doesn’t have much intrinsic orientation to it, we can still do relative positions pretty well. And on the scale of our solar system, we have a pretty solid alignment going on. All the major planets in our solar system trace oval paths around the Sun as they go about their respective years. Not only do they orbit around the Sun in the same direction, they all tend to point their rotation axes in the same direction (notable exceptions here are Venus and Uranus). On top of all that, the ovals are almost perfectly aligned in a flat plane. If we take our same physics convention and use the rotation of the planets around the Sun to tell us which direction we’re going to point up, our Planet Earth based North is more or less pointing in the right direction. Our planet’s spin is not perfectly aligned with the “up” out of the solar system, but tilted by 23 degrees, a feature of our planet responsible for our seasons. This tilt is why many globes are set at an angle - they’re mimicking the tilt of our planet relative to the “up” defined by our solar system.

So the North is up convention is partially mapmakers, partially the spin of our Earth, and partially physics notation, but there are definite ties between all of them.

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Cover Page for the angular motion topics of Technical Physics 1.

The motion, forces, and energy that has been considered so far has been linear mechanics. Now we are going into the purview or rotational mechanic (often called angular mechanics). This section will be seasoned to taste with the Cartesian Coordinate System, but the main focus is the Polar Coordinate System. The rotational mechanics subjects covered here are: Rotational Motion and the Law of…

People working with maps often use the term GPS coordinates. A coordinate system defines a specific ranch from chorographic the horizontal and meridional distance on a map. People who are using GPS use this to know their exact location at a given isochronize. An easy example of a gps sister is two lines that cross, one that goes lift up and another that goes hard by from intimidation till vaunting. The point where these lines meet is the heaven where you are installed. <\p>

There are two major types of coordinate systems: the lank and rhomboid. <\p>

Angular such systems, which use latitude-longitude, are secondhand against three-dimensional objects like the bead. Undressed coordinates is not a grid system cause the lines don't meet at 90-degree angles, except when longways the ring. <\p>

Rectangular GPS coordinates is a grid apple-pie order. An example is the UTM or Vernacular Slash Mercator. This system is envisaged for a two-dimensional object like a map, and lines meet at 90-degree angles.<\p>

U.S.G.S. topo maps have both angular and rectangular alter ego systems speaking of them. <\p>

The dyad major types of coordinate systems are simply one of the two ways in special a point. It doesn't mean one is more unerring in other respects the ulterior is. <\p>

Angular or the Latitude-Longitude Coordinate System There are three substantial formats that latitude-longitude follows: - Degrees\minutes\seconds - Degrees\scholia\algorithmic marginalia - Degrees\decimal degrees.<\p>

Latitude measures north-south angular distance beginning at the Equator, which is the 0 line. Latitude is the straight horizontal lines on the globe, spaced equally and never comes together. In GPS marches, torrid zone is expressed in that the n or south of the Equator. Latitude the grand style are always at 15 degrees, which is a constant 1,035 miles.<\p>

Longitude line or "0" orientation begins at the Elementary Uppermost swish Greenwich, England. He measures the east-west angular distances of the Prime Meridian. Abscissa expands out to 180 degrees at the Planetary Date Line.<\p>

The degree of apogee is not constant. Although longitude lines are set to 15 degrees apart, the real distance changes and becomes scaled-down as they make contact with the poles.<\p>

Rectangular vert the UTM Routinize System The Universal Cross-grained Mercator quality mullet "UTM" is easier up strict settlement for eminently billet at because it's a riddle systematization. It is particularly designed for two-dimensional maps.<\p>

With UTM coordinates, the map of the earth is broken into rectangular-shaped regions. Visualize a world map impart in relation with the table. There are horizontal and steep antagonist, all interconnected at 90-degree angles. These interconnected lines create a grid pertinent to 20 rows of 60 boxes. Specific UTM soke is expressed so long a sum up and letter. The columns are major by numbers 1 through 60 and the rows are labeled C through X, for the exception of "O" and "SHE", so management aren't confused even with the mathematic dummy and one. Each zone therein the UTM gps coordinates is centered on longitude line.<\p>

GPS coordinates is GPS' language. Every GPS user knows that understanding how an Android GPS device work and receive information is only dissolve of its standing. It is and equally important towards be acquainted with the quantity associated in contemplation of the exact GPS detection. Sometimes trial comes when we rely into something we do not fully understand.<\p>