Magnitude is a term derived from the Latin word magnitūdo , which can be translated as “greatness.” The concept is used to refer to the size of an element.
For example: “In the company we do not have space to install a machine of that size” , “It is difficult to park a car of that size” , “In this place you can find furniture of all sizes, so you will surely find a “appropriate product for your home.”
The notion is also used with respect to the relevance or seriousness of something: “The club had never achieved an achievement of such magnitude,” “To solve a problem of such great magnitude we need to have everyone's collaboration,” “I never thought that we would be facing a challenge of this magnitude.”
In the field of physics , magnitude is a property that can be measured . This means that these properties are assigned a value according to a measurement or a formula.
To measure a physical quantity it is necessary to use a standard in which it is well defined and then take this quantity as a unit. An example of this can be seen in the physical magnitude known as length , for which the International System of Units declared that the main standard is the meter .
Some quantities are basic and others are derived. Among the most common examples we have weight , velocity , mass, electric charge, energy, acceleration, time, density and temperature are examples of physical quantities. In short, we can say that it is any property that can be measured of a body or system.
The instrument with which the measurement of a physical quantity is carried out varies depending on the case. Take the case of a car: through different internal components, values of its various physical magnitudes such as engine temperature and fuel quantity can be known. On the other hand, with external tools we can determine the total weight of the vehicle, as well as its dimensions.
Through the International Vocabulary of Metrology , the International Bureau of Weights and Measures establishes that magnitude is an attribute of a substance, a body or a phenomenon that we can distinguish qualitatively and determine quantitatively. The units to express their value should not be written in italics, but the physical magnitudes should, as can be seen in the following example: in the expression m = 14 kg we write the "mass" variable as m , while the "kilogram" », as kg.
In the field of mathematics , meanwhile, a magnitude is a measurement that is assigned to an object that is part of a set. Unlike physical quantities, mathematical quantities can be defined abstractly.
For the Greeks there were various types of mathematical magnitudes, among which were the following: positive fractions, segments according to their length, polygons according to their surface, solids according to their volume and angles according to their angular magnitude.
They believed that it was not possible for the first two to be equal or isomorphic (they could not have the same structure ). Furthermore, for them negative magnitudes were not significant but rather the concept of mathematical magnitude was used especially when the lowest value was zero.
For each mathematical magnitude there is a function in which the measurable objects can be expressed, each of which corresponds to a numerical value . Typically, the magnitude of a number is known as its "module" or "absolute value," and in this case its sign is ignored since the magnitude is always positive.
Astronomy , finally, appeals to the idea of magnitude to refer to the logarithmic measurement that presents the relative intensity of the brightness emitted by celestial objects.