Do not understand Solution to this problem (AC Circuit Analysis)

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Discussion Overview

The discussion revolves around a homework problem related to AC circuit analysis, specifically focusing on the equations presented in the problem and their derivation. Participants express confusion regarding the application of concepts that may not have been covered in their current coursework, as well as the notation used in the equations.

Discussion Character

  • Homework-related
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants express uncertainty about the origin of the equations presented in the problem, noting that they have not encountered similar material in their current class.
  • There is mention of normalization constants from Fourier analysis and the use of square roots of 2, which typically indicates RMS values, but the logic behind these elements remains unclear to some participants.
  • One participant questions the use of "X" to indicate resistance, suggesting it may refer to reactance instead, and seeks clarification on the expression for the phase "u."
  • Another participant proposes that the problem may involve design approximations for inductive smoothing in a bridge rectifier context, indicating that the current waveform suggests effective smoothing.
  • Some participants note the clarity of the handwriting in the provided images, while others express difficulty in reading the text.
  • There is a suggestion to consult classmates for assistance with the formulas, emphasizing the value of peer support in understanding the material.

Areas of Agreement / Disagreement

Participants generally express confusion and uncertainty about the equations and concepts presented, with no consensus on their interpretation or application. Multiple competing views regarding the notation and underlying principles remain evident.

Contextual Notes

Participants indicate that prior coursework may not align with the current material, which could contribute to the confusion. There are also references to specific symbols and constants that may depend on definitions not universally agreed upon in the discussion.

Xyius
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Homework Statement


See The attached Images.

2. The attempt at a solution

The problem I am having with this is the following.

I do not know where he is getting these equations from. We haven't done anything like this in class. Although he keeps mentioning skills we learned in previous courses, which I took at another institution so it wasn't all exactly the same.

I see what looks like normalization constants from Fourier analysis? (2/pi) And square roots of 2 (usually indicates RMS). But I do not know the logic behind the equation. Also, why is he using "X" to indicate resistance? Is it a reactance? I also don't know where he gets the expression for the phase "u."

Sorry I know this might seem like a silly question but if anyone can help me out I would really appreciate it!
 

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Xyius said:

Homework Statement


See The attached Images.

2. The attempt at a solution

The problem I am having with this is the following.

I do not know where he is getting these equations from. We haven't done anything like this in class. Although he keeps mentioning skills we learned in previous courses, which I took at another institution so it wasn't all exactly the same.

I see what looks like normalization constants from Fourier analysis? (2/pi) And square roots of 2 (usually indicates RMS). But I do not know the logic behind the equation. Also, why is he using "X" to indicate resistance? Is it a reactance? I also don't know where he gets the expression for the phase "u."

Sorry I know this might seem like a silly question but if anyone can help me out I would really appreciate it!

X is the universal symbol of reactance: Z = R + jX. X = wL for inductor and -1/wC for capacitor. X is in Ohms.

I can't make out the text in the 1st (your work) slide.
 
It looks like this might be using design approximations used for inductive smoothing at the output of a bridge rectifier. The flattened current waveform suggests you can assume very effective smoothing. That constant current indicates why you can represent the load as a fixed voltage source: a steady current into a fixed load is just like a fixed voltage in opposition.

The topic may be discussed in your textbook, otherwise search for worked examples online.
 
Last edited:
The handwriting is very clear and easy to read on my tablet, anyway.
 
I do not know where he is getting these equations from. We haven't done anything like this in class. Although he keeps mentioning skills we learned in previous courses, which I took at another institution so it wasn't all exactly the same.
Have you asked others in the class about these formulae? In any subject, your best resource is always other students in your class.
 
NascentOxygen said:
The handwriting is very clear and easy to read on my tablet, anyway.
So's mine. I was referring to the printed text.
 

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