9.5.1
we consider electromagnetic waves confined to te interior of a hollow pipe, or wave quide.
We'll assume the wave guide is a perfect conductor, so that E=0 and B=0 inside the material itself,
and hence the boundary conditions at the inner wall are
E|| = 0
B ( it's perpendicular to surface of conductor ) = 0
The amplitude of a wave guide is independent of z because it is a characteristic property of a wave and is not affected by distance or position. This means that the amplitude remains constant as the wave travels through the guide, regardless of how far it has traveled.
The amplitude of a wave in a wave guide is determined by the initial conditions of the wave, such as the energy or intensity of the source. It is also affected by the physical properties of the wave guide, such as its shape, size, and material.
The amplitude of a wave guide does not directly affect the strength of the signal. However, a larger amplitude may indicate a stronger signal, as it represents a higher energy or intensity of the wave. The strength of the signal is also influenced by other factors such as attenuation and interference.
In most cases, the amplitude of a wave guide remains constant as the wave travels through it. However, in some cases, the amplitude may decrease due to factors such as attenuation or absorption. Additionally, if the wave is being actively manipulated or modulated, the amplitude may change over time.
The constant amplitude of a wave guide is important for maintaining the integrity of the signal. Any changes in amplitude can affect the accuracy and reliability of the signal, which is crucial in many applications, such as telecommunications, radar, and medical imaging.