Amplitude

  • In Physical traditional, one names amplitude measurement Scalaire (a coordinate) of a positive Nombre characterizing the width of the Oscillation of a Onde compared to its Median value.

  • In Mechanical quantum, one names amplitude a vector made up of a Module and a phase, which can be represented by a Complex number (two coordinates). The square of the module of this amplitude is comparable roughly speaking to a probability of detection of the particle in a given place.

Traditional physics

In this simple equation of wave:

there (T) = has sin ( T − K ) + B

has is the amplitude of the wave. It is the distance between the maximum of the wave and the horizontal axis.

The measuring unit of the amplitude depends on the measured physical size:

  • For a vibrating Cord, it is a distance.
  • For a sound wave, the amplitude corresponds to the pressure of the air, or the movements of the diaphragm of a high speaker. Its Logarithme is usually measured in dB, also a null amplitude is of - inf dB.
  • For the electromagnetic Radiation, the amplitude corresponds to the Electric field.
  • For a Electrical signal, the amplitude corresponds to the maximum value.

When one wants to measure the amplitude of physical phenomena, the amplitude such as it is calculated previously inevitably is not best adapted. This one is then called “amplitude peak” or “point of the amplitude”, distinguishing it from another concept of amplitude, used particularly in the electrotechnical : the quadratic Average of the amplitude compared to the horizontal axis.

various measurements of the amplitude of a sinusoidal signal

It is possible some to formalize the amplitude:

  • an absolute value of the extent of the disturbance of the point/particle the most disturbed by the wave on a cycle;
  • the absolute value of the extent of the displacement of a wave starting from a less value. Typically, the least value is taken as half of déplacementdéplacement;
  • an absolute value of a half of the least difference between maximum and minimum.

The third definition is often used for forms of “complex” wave. ( Why? )

to be made: to compare when/how there is equivalent or not, and when to use it humm a lab of Pine-1001 reveals the difficulty of the thing

Compare

Homonymy

Amplitude is also the name of a Video game for PlayStation 2.

Simple: Amplitude

Random links:Araméen | Cloranfenicol | The Community of communes of the One-eyed Valley | The Robber of nostalgia | Jean Péheu | Peter Geach | Chillicothe,_Iowa