Understanding the Different Units of Measurement

Measurement is a vital part of what we do on a daily basis. Subconsciously, we use it multiple times a day or even in just one transaction: from measuring kilograms in the kitchen to the more sophisticated amperes of electric current – we deal with measurment more often than we’re probably aware of. In fact, this article alone can be broken down, analyzed, and classified based on different factors that can be measured using data. In general, there are uniform variables applied all around the world that make measurements easy, functional, and comparable. However, standardized measurement principles did not exist until recently. To better understand this concept, here’s a brief look on the Different Units of Measurement as well as the history behind the art itself.

History of Measurement Principles

Measurement usually refers to the comparison of an unknown physical or chemical quantity with a quantity of a similar type taken as a reference using an instrument. Simply put, the process requires a reference frame and ultimately, units. Until the 18^th Century, there were numerous units deployed by different regions and countries. Such units were traditionally based on trading patterns and trading items. These various measurement principles had nothing in common with each other and proved to be immensely difficult for comparing information globally. The first unifying and logical system of measurement units only came after the French Revolution; called the metric system. A diplomatic treaty was set up which was named ‘The Metre Convention.’ The treaty internationally ratified the metric system on 20 May 1875 and became a significant moment in the history of measurement principles. The Metre Convention helped establish the Bureau International des Poids et Measures (BIPM). BIPM, which in turn, held Conférence Générale des Poids et Mesures (CGPM)  gathering experts that worked for the unification of a rational, consistent basis of measurement principles. During the eleventh CGPM conference, in 1960, the International System of Units (SI) was developed. SI included two broad classes of units:

• The seven base units that form the crux of measurement principles
• The derived base units

Before elaborating on the two classes, it is important to note that this system and classes of units are not exhaustive. In this age of scientific and technological advancements, the need for accurate measurements will continue to push responsible institutes towards improving all the current SI units. The definitions of these units are open to change as well as the addition of new definitions.’

The Base Units

The International System of Units, commonly known as SI, consist of seven ‘base’ units. These seven units represent the basic units of their respective physical quantities and serve as the comparison parameters for every other unit for that particular physical or chemical quantity. The SI base units and their representation symbols (denoted in brackets) are: Metre (m) The metre is the base unit for the length of an object or matter. Scientifically, the metre is the length of the path traveled by light in vacuum during a time interval of 1/299 792 458^th of a second. Kilogram (kg) The kilogram is the SI base unit for weight of a quantity or an object. A kilogram is the mass of the platinum-iridium prototype which was presented in the Conférence Générale des Poids et Mesures, held in Paris in  1889. Second (s) Second is the base unit for duration or period of time. Ampere (A) The ampere is the base unit for measuring the intensity of electrical current. Kelvin (K) Kelvin is the SI base unit for temperature. The Kelvin is the fraction 1/273,16 of the thermodynamic temperature of the triple point of water. Candela (cd) Candela is the SI base unit for luminous presence in a given direction by a source. Mole (mol) The mol is the amount of substance of a system.

The Derived Units

The base units provide the groundwork to expand on the measurement principles, in the form of the derived units. Such units are linked together to:

• Form a consistent system.
• Provide a wide range of values.

For instance, a single day is expressed as 24 hours (a derived unit) rather than 86,400 seconds (a base unit) to make it easier to understand. Some of the derived units with their symbols (in brackets) are: Electricity – Base Unit Ampere (A) Electrical resistance (R): ohm (Ω = V/A) Energy (W): joule (J) Mass – Base Unit Kilogram (kg) Volume (V): m^3 Pressure (p): Pascal (Pa) Force (F): Newton (N) Temperature – Base Unit Kelvin (K) Celsius (°C): t Unified measurement systems are probably some of the most successful collaborations in modern history. While learning all the metrics and equations can still be a handful for many, measurement itself has been largely automated thanks to technology and advanced calculations. What’s even better is that you can learn all about these principles and measurement tools through online training. It’s on-demand and accessible right from the comforts of your home or from your office. How eLearning measures up against traditional forms of education is subjective. But if efficiency and accessibility is your priority, then online is definitely the way to go.