## What is Length:

Longitude is the largest of the 2 main dimensions that flat things or figures have, as opposed to the smallest, which is called latitude. The term longitude is of Latin origin "latitudo”And, composed of“latus" What does it mean "wide, extensive”And the suffix "-Ia"Which expresses"quality of ".

In physics and mathematics, the length is the distance that joins 2 points and, through the length, the vertical length is obtained, it is what is known as height and, if a horizontal length is taken into account, it is synonymous with width .

The unit of measure for length is the meter. The Decimal Metric System is composed as follows: lengths less than the meter are: decimeter, centimeter, millimeter and, the lengths greater than the meter are: decameter, hectometer, kilometer and myriameter.

Also, in physics, wavelength is the distance in meters between 2 consecutive maximum or null values ​​of a wave. The length can be very small and is measured using a nanometer or angstroms up to 100 meters. The representation of the wavelength is as follows: λ (length) = c (speed) / f (frequency), it should be noted that the wavelength and frequency are inversely proportional, this means that high frequencies, lengths of small waves and vice versa.

In the medical area, the femoral length allows future parents and doctors to know if the fetus has adequate growth and weight in relation to the week of pregnancy. Femoral length is calculated in percentiles.

See more on Femoral Length.

## Longitude and latitude

In cartography, the longitude is the angular distance measured between the meridian of origin or Greenwich and the meridian that passes in the place. The value of longitude varies from 0 ° (on the Greenwich meridian) to 180 ° (opposite the Greenwich meridian), for east or west of Greenwich. In relation to the above, the Greenwich meridian is the 0 meridian and divides the earth into: western hemisphere and eastern hemisphere.

In each line of longitude, there is a time difference and the Greenwich Meridian is taken as a reference point to subtract or add minutes and thus determine the exact time of a place. The Greenwich meridian passes through the Royal Observatory of Greenwich, near London, in the United Kingdom, today it is converted into a tourist place, a museum, in which people take the opportunity to photograph themselves next to the metal line that represents to the indicated meridian.

Latitude is the angular distance measured between the equator and the parallel of a place, it varies between 0 ° (Equator) and 90 ° (at the poles) for the north or south, according to the hemisphere considered.

Longitude and latitude divide the earth into 4 hemispheres: north, south, east and west, in addition to determining the absolute location of any place on the earth's surface.