We use measure units (centimeters, seconds, kilograms, meters, etc.) every day. Measure units are essential to building cars, planes, phones, skyscrapers, and everything we can imagine. This means how we define these units is very important, and we have to have something to back them up. Today, we will talk about the three most important units according to the whole world except the United States, the meter, the second, and the kilogram.
First, let’s see the situation that led to having standard units. The fact is, hundreds of years ago, there were no rules for units. The first step happened where each culture had its own way of measuring things like elbows or feet. However, this method was not very useful, since these measures could vary greatly between people in the same culture. The next step was the rod, every culture or group of cultures had the rod of “name-of-culture” that was a Santander measure within that culture. Sadly, as trade progressed and the interaction between cultures became extremely important, the system once again was very difficult to use. The world had to wait until the french revolution to finally come up with the answer through the French Science Academy, which defined the units of measurement we use today, something no longer based on culture, but on the laws of nature.
- The meter
- The base for the meter is directly involved with the world we live in. A meter is a distance between the North Pole and the line of the Equator, passing through Paris, divided between 10 million.
- It is also really interesting to note that the original measure was made through the use of the Pythagorean theorem, measuring key points in the way and applying the well-known formula. Something amazing to do in an era with no satellites, and far less advanced technology.
- The Kilogram
- The kilogram was derived from the meter. A kilogram is defined to be the weight of the water in a cubic meter at 4 degrees celsius divided by 1000.
- This volume, likewise, is a liter. So if you ever wondered where the rule that a liter weighs 1 kilogram, it is exactly because that is how you define those units.
- The Second
- The second is perhaps the less interesting one of all the units. Since it is just the length of one day divided by 24, divided by 60, and then divided by 60 again. The pattern is obvious. As amazing as it seems, until the french revolution, not the whole world agreed on a unit of time.
Later in history, with the advancement of technology, and the need for new units like Volts, Ohms, Watts, bytes, etcetera, the world once again looked for things that happen in nature and defined units through the analysis of these phenomena. The organizations in charge since 1975 are the CIPM, the committee, the BIPM, the lab, and the CGPM, the conference where they are announced.