Kirchhoff's Law Violations: Transmission Line Equivalent Circuit

  • Thread starter Thread starter duniltmg1
  • Start date Start date
  • Tags Tags
    Line
AI Thread Summary
Kirchhoff's Voltage Law (KVL) and Kirchhoff's Current Law (KCL) are valid primarily when the transmission line length (L) is much smaller than the wavelength (λ) of the signal, specifically when λ >> L. KVL becomes invalid when time-varying magnetic fields induce electric fields, while KCL fails in scenarios where charge dispersion creates divergence in current density. Additionally, if the wavelength is comparable to or smaller than the line length, transmission line effects or antenna effects can occur, leading to power loss. These violations highlight the limitations of Kirchhoff's laws in high-frequency applications. Understanding these conditions is crucial for accurate circuit analysis in transmission line scenarios.
duniltmg1
Messages
3
Reaction score
0
Discuss under what circumstances kirchhoffs voltage law and kirchhoffs cureent law are no longer valid, and give an equivalent circuit for the tranmission line in those circumstances?
 

Attachments

  • jan 10 question 1.png
    jan 10 question 1.png
    3.1 KB · Views: 403
Physics news on Phys.org
I have found out that kirchhoffs voltage law and krichoff's current law are only vaild when the wavelength (λ) << L.
are there any other circumstances??
 
Discuss under what circumstances kirchhoffs voltage law and kirchhoffs cureent law are no longer valid, and give an equivalent circuit for the tranmission line in those circumstances?

a) it is only valid when the transmission line's length L is very small comparing to the wavelength (λ) of the wave passing through the transmission line.
 
KVL is invalid when time varying magnetic filed creates Electric Field.
KCL is invalid when Divergence of J is created by dispersion of a ball of charge placed inside a conducting medium.
 
(Merged 2 threads...)
 
duniltmg1 said:
I have found out that kirchhoffs voltage law and krichoff's current law are only vaild when the wavelength (λ) << L.
are there any other circumstances??

If L is the length of the wire, then this is not correct.

wavelength (λ) >> L.
The wavelength is has to be much greater than the length of the wires or there may be transmission line effects or even antenna effects where power is radiated and lost from the circuit.
 
Thread 'Have I solved this structural engineering equation correctly?'

Thread 'Have I solved this structural engineering equation correctly?'

Hi all, I have a structural engineering book from 1979. I am trying to follow it as best as I can. I have come to a formula that calculates the rotations in radians at the rigid joint that requires an iterative procedure. This equation comes in the form of: $$ x_i = \frac {Q_ih_i + Q_{i+1}h_{i+1}}{4K} + \frac {C}{K}x_{i-1} + \frac {C}{K}x_{i+1} $$ Where: ## Q ## is the horizontal storey shear ## h ## is the storey height ## K = (6G_i + C_i + C_{i+1}) ## ## G = \frac {I_g}{h} ## ## C...
View full post »

Similar threads

Engineering Can this circuit be simplified any further?
Replies
2
Views
1K
Engineering Can Kirchoff's laws and Ohm's law be used on circuits with diodes?
Replies
3
Views
12K
Engineering Find Currents I1 and I2 in an Electric Circuit
Replies
3
Views
3K
Solve Node Voltages Problem Homework
Replies
1
Views
1K
Engineering Voltmeter and ammeter calculation in a circuit
Replies
6
Views
5K
Engineering Why is the voltage source high potential into node 1 at -12 V in this op amp problem?
Replies
15
Views
2K
Solve Kirchhoff's Laws for Currents and Power Dissipation in a 3-Loop Circuit
Replies
8
Views
2K
Optimizing Mosfet Amplifier Problem Solution with Kirchhoff's Law and KVL
Replies
13
Views
2K
Engineering Finding a voltage in a circuit with only resistors and current sources
Replies
1
Views
3K
Engineering Kirchhoff's Law & Circuit Analysis: Q&A
Replies
9
Views
2K

Hot Threads

Recent Insights

Back
Top