Power loss in a transmission line

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SUMMARY

The discussion centers on the issue of power loss in transmission lines, specifically addressing the confusion surrounding the ABCD-Parameters for two-port networks. The participant reports an anomaly where the output power exceeds the input power, indicating a misunderstanding of the parameters A, B, C, and D. The solution involves solving for V1/I1 and V2/V1 with I2 set to zero, emphasizing the importance of clear notation and presentation of equations for effective communication.

PREREQUISITES
  • Understanding of ABCD-Parameters in electrical engineering
  • Familiarity with two-port network analysis
  • Basic knowledge of power calculations in transmission lines
  • Proficiency in algebraic manipulation of electrical equations
NEXT STEPS
  • Study the derivation and application of ABCD-Parameters in two-port networks
  • Learn how to perform power calculations in transmission lines
  • Explore techniques for presenting mathematical equations clearly in discussions
  • Investigate common pitfalls in electrical engineering problem-solving
USEFUL FOR

Electrical engineering students, educators, and professionals dealing with transmission line analysis and power calculations will benefit from this discussion.

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Homework Statement


upload_2018-12-3_22-24-41.png


Homework Equations

The Attempt at a Solution


upload_2018-12-3_22-25-13.png


I have posted the whole solution so it is more complete, but I really only need help with part c (I think)

My output power is higher than my input power, I'm not sure where I'm going wrong
 

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I have no idea what the information regarding A, B, C and D means. Do they refer to a diagram or is this some standard notation for such problems?
 
haruspex said:
I have no idea what the information regarding A, B, C and D means. Do they refer to a diagram or is this some standard notation for such problems?
I believe they refer to the ABCD-Parameters for a two port network:
upload_2018-12-4_14-38-15.png
 

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I'm sorry but I can't make out your writing. You should type everything in unless you have particularly large and clear writing. You don't have to learn latex necessarily; click on the summation sign (upper case sigma) for lots of symbols.

You can solve for V1/I1 and V2/V1 with I2 = 0 in the post 3 equations to get all the answers.
.
 
rude man said:
unless you have particularly large and clear writing.
Even then, it is hard making comments on lines of algebra in the middle of images (unless the equations are numbered in the image).
 

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