Before entering fully into the clarification of the meaning of the term wave
amplitude, it is interesting that we proceed to determine the etymological
origin of the two main words that shape it:
-Amplitude, first of all, derives from Latin. Specifically, it comes from
“amplitudo”, which can be translated as “extensive quality”. In the same way, it
should be noted that this term is the result of the sum of two components: the
adjective "amplus", which is synonymous with "extensive" or "wide", and the
suffix "-tud", which is used to indicate quality.
-Onda, on the other hand, is a word that comes from the Latin, exactly from
"unda", which is equivalent to "wave".
The notion of spaciousness can be used to name the
lengthening, stretching, or widening of something. It is called wave,
moreover, to the movement propagation takes a fluid to the elevations formed by
the disturbance of the surface of a liquid substance and the manner of
propagation having electric and magnetic fields in space.
the concept of wave amplitude appears in the field of physics and
is linked to the highest value that a variable registers,
measured from the midpoint or equilibrium. In an
electromagnetic signal or wave motion, the wave amplitude is the distance
between the maximum value (the highest point of the wave) and the equilibrium
The wave amplitude can be seen on a graph with a sinusoidal
curve in the Cartesian coordinates. If we take the X axis as
the midpoint, the wave amplitude will be given by the space that exists between
the highest point on the Y axis that touches the sinusoid and
the mentioned X axis.
A physical disturbance, in this way, can be plotted on a model as a magnitude
whose value changes over time. Wave amplitude is noted when analyzing the values
according to the points occupied by the disturbance (graphed as a wave) in space.
In the case of sound waves, the wave amplitude reveals the
distance between the wave peak (the highest value) and its base, measured in decibels. As
the wave amplitude increases, the decibels increase, reflecting a growth in the intensity
of the sound.
There is another important series of aspects that must be known about the
mentioned wave amplitude. Specifically, we can emphasize that the units to
measure it will vary depending on the type of wave to which we are referring:
-When it is a mechanical class wave, we will resort to the use of what are the
units of length to measure it.
-In the case that you are working with an electromagnetic wave, what you will do
to measure the amplitude will be to use a unit that responds to the name of
-If, on the other hand, we are referring to alternating current waves, we will
resort to using amps and volts in their measurement.
-When we are dealing with sound waves, what will be done is to choose to opt for
what are units such as the millibar, the pascal or the set of remaining units.