We explain what power is in physics and mathematics. Also, what is a world power and other senses of the term.
What is potency?
The concept of power exists in different fields of human knowledge, such as philosophy, the physical, the math or even in different areas of daily life. In all cases, however, it has a similar meaning, linked to the ability to execute an action, to produce an effect or to unleash a force. Thus, having power implies also having these capacities, that is, having can.
The word power comes from Latin, specifically from the voice power (“to have power”), derived from the verb pose ("can"). That was the translation that the Romans gave to the Greek term dunamis (δύναμις), used by philosophers like Aristotle to designate capacity or possibility, depending on the context.
In the Aristotelian work, in fact, two meanings of power are differentiated: a weak one, which alludes to the fact that something could simply happen; and another strong one that implies that things are given to do something well or to do something completely.
Later, Aristotle differentiated the potentiality (possibility) of things and beings, their ability to do something, from the realization of said possibility, that is, their actuality (performance). These considerations were key to the history of Western thought and especially to the founding of disciplines such as physics, responsible for studying the movement, the Energy and the worked.
power in physics
In the field of physics, dedicated to the study of natural forces, the term power (represented by the letter P) means a certain amount of work (W) performed, expressed in joules (J), with respect to each unit of weather (t) determined, expressed in seconds (s).
This means that the power of a body is the amount of work that said object performs per unit of time, that is, the strength that it prints on another body, the energy that it transforms, etc. That is why its generic calculation formula is P = W/t. The unit in which power is measured is the watt or watt, equivalent to 1 joule per second (1 w = 1 j/s).
However, power acquires very specific meanings in the different branches of physics:
- In the mechanics, power means something very similar to the above: the amount of force that is applied to a body to induce a certain amount of movement (and therefore, a certain speed). Therefore, the formula for calculating mechanical power is P = F. V, where F equals force (expressed in Newtons: N) and V equals speed (expressed in meters per second: m/s).
- In the electricity, power is understood as the amount of electric power that is transferred by an electrical circuit per unit of time, that is, the rate at which energy is delivered or absorbed by a given element. It is expressed in kilowatts per hour (Kw/h), but its calculation methods depend on whether we are talking about DC (CC) or from alternating current (AC).
- In the thermodynamics, heat power is understood as the amount of heat that a body emits, that is, releases to the environment, for each unit of time that passes. For its calculation, the formula P = E / t is used, where E is equal to the heat energy expressed in joules (J), and t is equal to the amount of time expressed in seconds (s).
- In acoustics, it is called acoustic power or sound power to the amount of energy that a vibe sound is capable of transporting through a given environment or medium, per unit of time. Its value depends largely on the wavelength, since the shorter the wavelength, the greater the concentration of energy in the waves, and therefore it is determined by the source itself that emits the sound. When we hear a sound, its “volume” is equivalent to our perception of acoustic power, expressed in decibels (dB).
power in math
In the power, the base is multiplied by itself the number of times indicated by the exponent.In the field of mathematics, a power is called an arithmetic relationship between two terms: a base (a) and an exponent (n), in such a way that the base is multiplied by itself the number of times indicated by the exponent.
This is expressed as follows: an, and is often read as “a raised to the n” or “a to the nth power”, using ordinals to refer to the exponent. In other words, 24 is read “two raised to the fourth power” and is equivalent to 2 x 2 x 2 x 2 (that is, 8); while 35 is read “three raised to the fifth” and is equivalent to 3 x 3 x 3 x 3 x 3 (that is, 243).
There are two exceptions to this reading method: when the exponent is 2, it is read as “squared” and when it is 3, it is read as “cubed”. Therefore, 52 is read "five squared," while 53 is read "five cubed."
World power
In international relations, it is called World powers or great powers to nations that are important enough on a global level to impose their own rules of the game and that also have the necessary resources to defend them.
The world powers are, in some way, the "protagonists" of the world political narrative, and exercise a relationship of hegemony or subordination over weaker or dependent nations.
Therefore, a world power is a State that generally has economic, technological and military power, sufficient to be taken into account as an influential actor in the concert of nations.
Consequently, there are often relations of tension and rivalry between them, but also of cooperation and alliance. When a world power becomes a power within powers, it is known as a superpower.
Currently, at the beginning of the 21st century, the consolidated world powers are: Germany, the United States, France, India, Japan, the United Kingdom, Russia and China. Among them, only China and the United States qualify as “superpowers”, due to their enormous military power, their technological deployment and their economic importance.
Other common uses of the term
There are other uses for the word power in very specific contexts and expressions, such as:
- Locomotive power, referring to the ability of a vehicle to reach high speeds and move at full speed. For example: "The engine of my old Fiat had much more power than this one."
- Sexual potency, which refers to the ability of a person (generally male) to satisfactorily comply with the sexual act, that is, to have and sustain an erection. For example: "There are very good exercises to recover sexual potency."
- To be something in potential, an expression that means that someone is capable or has all the probabilities to be or do something determined, which does not necessarily mean that he has done it. For example: “Miguel is a murderer in power”.