What do the telegraph equations physically describe?

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In summary, the conversation discusses the relationship between the telegraph equations and Maxwell's equations in describing electromagnetic waves. They both involve the use of capacitance and inductance, but the telegraph equations focus on small parts of a medium while Maxwell's equations consider the entire medium. It is peculiar that these approaches result in the same wave motion. The presence of a resistor in a circuit is communicated through reflected waves according to the telegraph equations. The exact mechanism of wave motion is unclear, as it could be influenced by the fields of electrons or the potential at different positions.
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are derived in my book from the assumption that a wire can be cut into a lot of infinitesimal wires with a capacitance and inductance each.
Can someone explain to me what these physically describe? What is it that travel with the speed of almost light. I don't think it's the drift velocity so it must be the information that the fields have changed back at the battery or something like that. But that should mean that the waves they describe are equivalent to the ones predicted by decoupling maxwell's equations. If so, that is just weird. Maxwell's equations have assumed nothing about the wires and their self-inductance and capacitance, so it's just weird that they should give the exact same.
Also my book discusses how if you turn on voltage at the end of a circuit how the presence of a resistor later on the circuit is communicated via the telegraph equations. I want to understand this: Is it the bouncing of the physical electrons and their pushes against each other which communicates the presence of a change in the cable or is it the fields or something like that. Please just say as much as you can about this phenomenon because I don't really get it.
 
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The Telegraph equation is a special case of the Transmission line equation with zero series inductance and zero parallel leakage. It also resembles the heat conduction equation.

It describes an electromagnetic wave traveling in guided conditions, so yes, it is allied to Maxwells equations.

A change of characteristic impedance, such as a resistor, results in a reflected wave. That is how the resistor is detectable at the origin.
 
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but why is it intuitively that the telegraph equations describes the same wave as the maxwell equations. Maxwells wave equations are derived by decoupling his field equations and then applying to them the boundary conditions involved with a medium. The telegraph equations looks at capacitance and inductance for small parts of a medium. It is just weird that these approaches are connected on such a deep level.
And can you tell me what it is that does a wave motion? Is it the fields of the electrons or the potential at different positions (as in the telegraph equations) or what is it?
 

1. What are the telegraph equations?

The telegraph equations are a set of partial differential equations that describe the propagation of electrical signals in a transmission line. They were first derived by James Clerk Maxwell in the 1860s and have since been used to analyze and design communication systems.

2. What is the significance of the telegraph equations?

The telegraph equations are significant because they provide a mathematical model for understanding and predicting the behavior of electrical signals in a transmission line. This is crucial for the development and improvement of communication technology, such as telegraphs, telephones, and modern data transmission systems.

3. How do the telegraph equations work?

The telegraph equations describe the relationship between voltage and current along a transmission line, taking into account the effects of resistance, capacitance, and inductance. They can be solved to determine the characteristics of the signal, such as its speed, attenuation, and distortion, as it travels through the line.

4. What are the limitations of the telegraph equations?

The telegraph equations assume a linear, time-invariant system and do not account for nonlinear effects or changing system parameters. They also do not take into account external factors, such as electromagnetic interference, which can affect the transmission of signals.

5. How are the telegraph equations used in modern technology?

The telegraph equations are still used in modern communication systems to analyze and design transmission lines, such as coaxial cables and optical fibers. They are also used in the development of high-speed data transmission technologies, such as DSL and Ethernet, to ensure efficient and reliable communication.

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