Electronics > Beginners
Dumb question about resistors in series/parallel
<< < (5/6) > >>
IanB:

--- Quote from: Hero999 on May 02, 2018, 12:14:34 pm ---The other methods such as nodal and mesh analysis work too and arguably are easier to apply, once one is familiar with them, but I prefer my method which I find more intuitive. Indeed, I'd have to consult a textbook if I had to perform mesh and nodal analysis, as I've not done them since college.

--- End quote ---

Another method I'd like to try myself when I have a free moment is to use the Δ-Y formula to convert the Δ arrangement of R1, R3 and R5 into the equivalent Y network, which then makes the whole network much easier to reduce.
IanB:

--- Quote from: Brumby on May 02, 2018, 11:26:40 am ---To TheN00b - Don't let that ^ ^ ^ scare you.

You will be able to cope with that a bit further down the road.  When you get there, it will be another challenge to learn, but it will provide you with the ability to solve seemingly impossible problems.

--- End quote ---

This. You are seeing things here that are way beyond what you are expected to learn in high-school physics  :)
Kirr:

--- Quote from: IanB on May 02, 2018, 01:23:02 pm ---
--- Quote from: Hero999 on May 02, 2018, 12:14:34 pm ---The other methods such as nodal and mesh analysis work too and arguably are easier to apply, once one is familiar with them, but I prefer my method which I find more intuitive. Indeed, I'd have to consult a textbook if I had to perform mesh and nodal analysis, as I've not done them since college.

--- End quote ---

Another method I'd like to try myself when I have a free moment is to use the Δ-Y formula to convert the Δ arrangement of R1, R3 and R5 into the equivalent Y network, which then makes the whole network much easier to reduce.

--- End quote ---
Yes, Δ-Y as well Y-Δ has to be mentioned. So let me just expand a bit on this method, for completeness.

Suppose all available serial and parallel arrangements of resistors are already simplified, and the network is still not a single resistor. What to do next? One simple approach is to apply Δ-Y and Y-Δ transforms. Y-Δ is actually a 3-resistor case of a more general star-mesh transform. While Δ-Y is sometimes more convenient, star-mesh transform has some nice properties: 1. It is always applicable. 2. It always removes one node, leaving you with a smaller network. This means the repeated application of star-mesh transform (followed by parallel and serial simplifications when possible) will slowly but surely solve any finite network.

This method is quite mechanical - it does not require thinking about equations or Kirchhoff's laws or much of anything else. So this approach is used in my solver (linked in my sig) - this tool can walk you through this method step by step.
Kirr:

--- Quote from: IanMacdonald on May 02, 2018, 07:04:58 am ---Interesting point is that some of these resistor networks are solvable, some are not, or are incredibly difficult to solve. For example an extra resistor between the junctions of R2/R3 and R6/R7 turns this into an entirely different proposition.

--- End quote ---
Decided to try it. Spoiler link - click to check answer or give up. (Since the new resistor is unspecified, I took the liberty to choose a value of 147 Ω).
TheN00b:

--- Quote from: BravoV on May 02, 2018, 04:20:53 am ---
--- Quote from: TheN00b on May 02, 2018, 04:16:47 am ---I'll do my best to not be scared. Can't guarantee much though. Lol

--- End quote ---

LOL .. yeah, it will take a while, practice frequently will make it feels natural, trust me.

One thing for sure, now you've learned or at least realized on how NOT to draw a schematic that sucks.  :P

--- End quote ---
And if I do encounter one (probably won't) at least I know how.. who knows, it could be extra credit?



--- Quote from: Brumby on May 02, 2018, 11:26:40 am ---To TheN00b - Don't let that ^ ^ ^ scare you.

You will be able to cope with that a bit further down the road.  When you get there, it will be another challenge to learn, but it will provide you with the ability to solve seemingly impossible problems.

--- End quote ---

Goodness, I hope so! I want to pursue an EE major someday, so it might be best to learn now though.

Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod