What’s the equivalent of the terms horizontal and vertical in the third axis?
Is longitudinal what you’re looking for?
Horizontal isn’t a single, one-dimensional direction. It is a plane- there are an infinite number of lines in that plane that could be considered “horizontal.”
This is true. But the way I read the OP was as if he were looking at a three-dimensional graph. The X-axis is horizontal, the Y-axis is vertical, and the Z-axis is…? Well, it’s also horizontal.
But if you move the axes to an aircraft where the origin passes through the CG, then you have the longitudinal axis (roll), lateral axis (pitch) and vertical axis (yaw).
Lateral is the term I see used most often.
Johnny L.A. is right - I meant in terms of a graph. The x axis is usually the horizontal one, the y axis is vertical, so what’s the z axis?
I actually thought up a couple more questions.
When a straight line moves through both a vertical and a horizontal plane, then it’s a diagonal line. Is diagonal the term used for any combination of two axis? How about with a line moving through all three planes?
In those 3-dimensional systems, “horizontal” isn’t a direction- lateral and longitudinal are (although everything that doesn’t have a vertical component is horizontal).
Another system, which I used in a former job, was Range, Azimuth, and Elevation.
Now this may be a carpenter’s term more than a mathematician’s, but I would say “depth” describes what you’re trying to say.
I think the posts already given indicate that the reference system is needed before the accurate term can be applied. My first reaction to the OP was “depth” but the other posts have given me pause.
How about simplifying the issue? If you’re moving in the horizontal direction, most likely it’s a “left-to-right” or “right-to-left” motion. Vertical movement would involve “up and down” actions. The other direction would be “front-to-back” or “back-to-front.” I can see how the “horizontal plane” might confuse the two non-vertical directions, but if the reference system could be seen as directions to an apartment in a building on such-and-such a street, the directions might include something along the lines of:
Go down 13th street to 125 (horizontal)
Go up to the fourth floor (vertical)
Go down the hall to number 266 (whatever it’s called)
I can’t provide a unique term for that movement, but I suspect the lack of precision comes from the way that “down” and “up” serve multiple purposes.
Not much help, I’m sure.
However, locating a place on the planet involves longitude, latitude and altitude in whatever degree of precision is required for specific location.
ScoobyTX said horizontal and vertical are planes, and he’s right. And these planes are defined relative to the surface of the earth.
Horizontal means lying in a plane parallel to the local surface of the earth. A horizontal line, therefore, is contained entirely in a plane parallel to the earth’s surface at that point.
Vertical means something is perpendicular to the earth’s surface. It’s insufficient to say that it’s contained in a single plane that’s perpendicular to the earth, because it could still be “leaning.” In fact, think of the Leaning Tower of Pisa, or more specifically, the line through its axial center. You can imagine a vertical plane that contains that line, but the line itself is not vertical because there needs to be another. If a line is in two vertical planes, it’s vertical.
So while it’s insufficent to be in one perpendicular plane to be considered vertical, a line can be in just the one parallel plane and be considered horizontal. That’s because there are an infinite number of intersecting planes that are perpendicular to the surface, but only one parallel plane for any altitude.
The issue is that “vertical” takes up two orthogonal dimensions to qualify it. Something is horizontal just because it’s got the same altitude everywhere. But something is only vertical is it’s got the same latitude and longitude everywhere. that’s why three dimensions collapse to just two measures of “squareness.” The loss of disctinction in latitude and longitude, along the earth’s surface, happens because the earth is closed, and speherical, so every point is the same as every other point.
However, if the earth were a cube, you could define three distinct orientations that corresponded to planes parallel to: (1) the xy plane, (2) the yz plane and (3) the xz plane.
Ok, clarifying. Taken from what people have already said, the systems are;
Width - Height - Depth
X-axis - Y-axis - Z-axis
Left-to-right - Up-and-Down - Forwards-and-Back
Pitch - Yaw - Roll (uhm, I think)
Range - Elevation - Azimuth (again, I think)
So;
Horizontal - Vertical - ?
What’s the equivalent term? Or (as I think some people are saying) is horizontal/vertical not the same kind of system as the others?
aerodave - I think I get what you’re saying, and the gist is vertical-horizontal is a different system to the other examples. Is that correct? (sorry, it takes me a while to picture things like this).
Longitude, latitude, and altitude?
http://boards.straightdope.com/sdmb/showthread.php?t=63456&highlight=longitude+latitude
Vertical isn’t a plane- it is a single line. It’s local meaning can be defined by a line passing through the center of the earth and a point on the surface of the earth (let’s call it P[sub]s[/sub]). The corresponding horizontal plane could be defined as a plane perpendicular to this vertical line at P[sub]s[/sub]. A north-south direction could be further defined as a line within this plane which is tangent to a great circle passing through the P[sub]s[/sub] and the surface intersection of the rotational axis of the earth. East-west would be defined as a line within the horizontal plane and perpendicular to the north-south line.