Height

Height refers to the distance of an object point from a reference line or surface. It is a one-dimensional size, and one of the three spatial dimensions, which are in units of length (usually in meter ) shown.

For all of the physical objects on the ground, the altitude is the vertical distance from a reference surface, which assumes a perpendicular direction. This is true in a broader sense for all bodies in a gravitational field, which sets a frame of reference for top-bottom.

Height of an object

Generally, the geometrical height is the greatest distance from a base line (as in the plane triangle ), or a base, that is the maximum of all the normalized distances of all points. The value is then called the total height of the object. Does this apply for a point to, this is the tip of the object.

• Example, the dimensions of an object in logistics, as well as in common parlance

This comes in technical applications, the surface of the earth as a reference considered ( height above ground ):

• In buildings such as the height of the building measured to a level point as the height of the building, and the ridge height to the top of the roof on the building codes in the reference. At about skyscrapers, the addition still wear high antennas on height records are also up to the uppermost tip measured ( structural height ); see Tallest Building.

Altitude

In geodesy to use different height systems for the altitude to which different height definitions and reference areas are based. For the indication of terrain heights ( engl. elevation ) these reference areas shall be made ​​mostly to mean sea level measured at one level.

Therefore, the earth sciences differ in absolute height and relative height:

• The absolute level is the "height above zero ": Height above sea level ( m above sea level. NN, m above sea level. A. m above sea level. M. ) in relation to a specified as zero survey marks. Since the systems of different countries on different nodes, and even different seas refer, created at the state borders a jump in altitude.
• The higher the ellipsoidal geodesy, dynamic, orthometric, normal - orthometric and normal height relative to a figure of the earth; see Elevation (geodesy )

As an example of the difference is considered here the " highest mountain in the world ", generally of Mount Everest, which is discretionary in absolute height of 8,848 meters above sea level, but in relative height to the foot of the mountain on deepwater reason this is the volcano Mauna Kea, a summit of the massif that forms the island of Hawaii. In addition, there are other bases for the height ( center of the earth as an absolute level in relation to an idealized as a spherical earth) or Vertical separation; refer Highest mountain.

More height relations

• At altitudes is called the height above ground with AGL ( above ground level, height), the height above sea level (MSL mean sea level, altitude ), and height, in relation to flight level as FL ( flight level )
• In the railway sector is measured on top of rail, road traffic at street level (middle top edge top layer )

• Height is also the abbreviation for elevation angle (usually in degrees or radians) about the astronomical height of a star above the astronomical horizon, or the latitude ( = latitude ).

Altimetry

The level measurement can be done by leveling, Surveying, GPS or barometric. Special equipment for measuring altitude are called Altimeter.