Convert millimeter to meter

Symbol

The millimeter is represented by the symbol "mm." 

Description

Millimeter is an SI (International System of Units) unit of length. It is usually the smallest measure in rulers of the metric system.The word "milli" is derived from the Latin word mille, which means one thousandth. Therefore, a meter is equivalent to a thousand times a millimeter.

The international definition of meter which is the SI base unit of length, is the length of path that light takes in the vacuum over a period of 1/299 792 458 of a second. Thus, 1 millimeter is equivalent to 1/1000 meter. That implies that a millimeter is the distance that light travels in the vacuum in 1/299792458000 seconds.

Following that, there are 10 millimeters in a centimeter and 100 millimeters in a decimeter. In the other direction, a millimeter is equivalent to 1/10 centimeters. A millimeter is also equivalent to 1000 micrometers.

Interestingly the smallest dimension human eyes can detect is about 0.02 to 0.04 mm. This is about the thickness of human hair!

History

The term millimeter was first used in the late 1700s. It was introduced during the development and adoption of the metric system of weights and measures in France in 1795.

The first recorded use of the millimeter was in the Journal of Natural Philosophy in 1797, according to OED (Oxford English Dictionary).

Use

Millimeter is a very small unit of measure. Therefore it is usually used for measuring minute dimensions. 

Symbol

The meter is represented by the symbol ‘m’.

Description

Meter is the base unit of length in the SI system (International System of Units). The term meter was originally derived from the Greek words "metreo" (verb form) and "metron" (noun form) meaning "measure”.

The length of the path that light takes in the vacuum in 1/299792458 seconds was the official definition of a meter from 1983 to 2019. As of 2019, the meter has been redefined as the length of the path traveled by light in a vacuum during a time interval of 1/299792458 of a second where a caesium hyperfine transition frequency defines the second.

Hence, the difference between the old and new definitions of meter is the addition of the definition of the second. However, interestingly the definition of the meter fixes the speed of light in a vacuum to the exact value of 299,792,458 m/s. 

Meters can be changed to other SI units using prefix multipliers based on powers of ten. For example, a meter consists of 100 centimeters, and one thousand meters equals a kilometer.

To convert m to in (meter to inches), you will need to multiplu the meter by 39.37 since  a meter equals 39.37 inches. Let's talk about large unites and how meter looks in comparison to them. 1609 meters is equivalent to a statute mile. 

History

The French first used the unit meter in the late 1700s. On March 30, 1791, the French Academy of Sciences specified the length of a meter. 

However, it was officially defined in 1799. In 1983, the meter was defined as it is measured now. But in 2019, the addition of the definition of second was added to it to reducec uncertainity.

The English word 'metre' was first used at the beginning of 1797. It was first measured with an interferometer by Albert A. Michelson in 1893.

Use

Meter is used for length, height, width and thickness measurement of objects in countries that follow SI units. However, in the states it is not used commonly.