毫克到千克换算

Milligram

Definition: A milligram is a unit of weight and mass that is based on the SI (International System of Units) base unit of mass, the kilogram. It is equal to 1/1,000 grams, or 1/1,000,000 kilograms.

History/origin: The milligram is based on the SI unit of weight and mass, the kilogram. As an SI unit, it uses the "milli" SI prefix to denote that it is a submultiple of the base unit. Although the "milli" prefix denotes a submultiple with respect to the gram, the kilogram, not the gram, is technically the SI base unit of mass.

Current use: As a submultiple of an SI base unit, the milligram is widely used in many applications, from everyday use to measure the weight or mass of foods, substances, etc., to widespread use in scientific labs, among other areas.

Kilogram

Definition: A kilogram (symbol: kg) is the base unit of mass in the International System of Units (SI). It is currently defined based on the fixed numerical value of the Planck constant, h, which is equal to 6.62607015 × 10^-34 in the units of J·s, or kg·m²·s^-1. The meter and the second are defined in terms of c, the speed of light, and cesium frequency, ΔνCs. Even though the definition of the kilogram was changed in 2019, the actual size of the unit remained the same. The changes were intended to improve the definitions of SI base units, not to actually change how the units are used throughout the world.

History/origin: The name kilogram was derived from the French "kilogramme," which in turn came from adding Greek terminology meaning "a thousand," before the Late Latin term "gramma" meaning "a small weight."

Unlike the other SI base units, the kilogram is the only SI base unit with an SI prefix. SI is a system based on the meter-kilogram-second system of units rather than a centimeter-gram-second system. This is at least in part due to the inconsistencies and lack of coherence that can arise through use of centimeter-gram-second systems, such as those between the systems of electrostatic and electromagnetic units.

The kilogram was originally defined as the mass of one liter of water at its freezing point in 1794, but was eventually re-defined, since measuring the mass of a volume of water was imprecise and cumbersome.

A new definition of the kilogram was introduced in 2019 based on Planck's constant and changes to the definition of the second. Prior to the current definition, the kilogram was defined as being equal to the mass of a physical prototype, a cylinder made of a platinum-iridium alloy, which was an imperfect measure. This is evidenced by the fact that the mass of the original prototype for the kilogram now weighs 50 micrograms less than other copies of the standard kilogram.

Current use: As a base unit of SI, the kilogram is used globally in nearly all fields and applications, with the exception of countries like the United States, where the kilogram is used in many areas, at least to some extent (such as science, industry, government, and the military) but typically not in everyday applications.

毫克到千克转换表

如何转换毫克到千克

1 m克 = 1.0E-6 千克
1 千克 = 1000000 m克

示例: 将 15 m克 转换为 千克：
15 m克 = 15 × 1.0E-6 千克 = 1.5E-5 千克

常用的重量与质量单位转换