Which country invented the metric system?

The meter unit was invented in France. 1790 In May, a special committee composed of French scientists suggested that one fortieth of the total length of the earth meridian passing through Paris should be used as the unit of length-meter, and 179 1 year was approved by the French Parliament.

In order to make the reference instrument of primitive rice preserved by the International Bureau of Metrology, under the leadership of French astronomers Gerliangbule and Mishin, measurements were made from Dunkirk, France to Barcelona, Spain, and from 1792 to 1799.

1799, according to the measurement results, a platinum measuring ruler with a short section of 3.5mm× 25mm was made, and the distance between the two ends of the rod was set as 1m, which was kept by the French archives, so it was also called "file ruler". This is the earliest definition of rice.

Unit of measurement conversion:

1 m = 10 decimeter; 1m = 100cm； 1m = 1000mm； 1 decimeter = 10/0cm; 1 decimeter = 100 mm; 1 cm = 10/0mm.

Commonly used length units are: kilometer, kilometer (km), decimeter (dm), centimeter (cm), millimeter (mm), micron (micron), nanometer (nm), picometer (pm) and femto meter (fm).