ABSTRACT
Amplitude, A: Is the maximum displacement of the wave above or below the position of equilibrium. The equilibrium position is the middle position, or level, about which the system is oscillating in a periodic manner. For a wave described by the following sine equation:
y = A sin(kx – ωt), (11.1)
where A is the amplitude of the wave, and the argument (kx – ωt) is its phase. Intensity, I: The energy intensity of a wave, that is, energy perunit area per unit time is pro-
prtional to the square of the absolute value of its ampliude. Thus for the wave, described above, the intensity I is
I ∝ |A|2. (11.2)
The intensity of a wave will be discussed separately in Section 11.4.
