## 0730: "Circuit Diagram"

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modularblues
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### Re: "Circuit Diagram" Discussion

glitterbug12 wrote:This amuses me... reminds me of this piece.

Oh yes, completely analogous... you beat me to this one. And the 666 timer made me speechless.

Invertin
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### Re: "Circuit Diagram" Discussion

I loved "not a resistor, wire just does this" in particular. Mainly because I'm not an electical engineer or anything like that and don't know what most of the other stuff would or would not do.

MoreOrLess
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### Re: "Circuit Diagram" Discussion

Everyone can rest easy; I have done the hard work for you. The equivalent resistance of the mass of resistors (to 4 places) is 0.7479 Ohms! How did I do it? As my profs used to say, that is an exercise left for the students to solve.

phillipsjk
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### Re: "Circuit Diagram" Discussion

Did you get the number on that truck?

MoreOrLess
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### Re: "Circuit Diagram" Discussion

No I missed that post. Had I seen it, I would not have bothered to enter the circuitry into a freebee spice clone.

Arancaytar
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### Re: "Circuit Diagram" Discussion

glitterbug12 wrote:This amuses me... reminds me of this piece.

The "remove cattle from stage" direction is my favorite.
"You cannot dual-wield the sharks. One is enough." -Our DM.

enjoyeverysandwich42
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### Re: 0730: "Circuit Diagram"

Still don't see the flux capacitor.

Where I live, I95 does split for a good long while

Love the thunderdome reference, the 666 timer, and the other small handful of joke I get after one semester of digital, sure I'm still missing a good amount though.

GenericAnimeBoy
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### Re: "Circuit Diagram" Discussion

forrestv wrote:
http://im.forre.st/resistors.jpg

I got 347 ohms for that circuit made of 463 ohm resistors, so 347/463 or about 0.749 ohms.

Epic, sir. Truly epic. How long did that take?
In light of the impermanence and absurdity of existence, I surmise that nothing is better for us than to rejoice and to do good in our lives, and that everyone should eat and drink and enjoy the good of his/her labor. Such enjoyment is a gift from God.

SteevyT
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### Re: "Circuit Diagram" Discussion

Steve the Pocket wrote:
helo darqness wrote:sometimes xkcd lowers my self-esteem, as comics like this are so esoteric, i feel completely out of the loop and uneducated.

It's not supposed to mean anything; it's just a fake circuit design made out of nonsense.

Basically it's the electrical engineering equivalent of http://www.whitetreeaz.com/gibber/faeries_aire_and_death_waltz.jpg]this little beauty.

The percussion instructor here is going to see that.

(weird, wouldn't let me post without breaking the link)

paramecium
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### Re: "Circuit Diagram" Discussion

SteevyT wrote:
Steve the Pocket wrote:
helo darqness wrote:sometimes xkcd lowers my self-esteem, as comics like this are so esoteric, i feel completely out of the loop and uneducated.

It's not supposed to mean anything; it's just a fake circuit design made out of nonsense.

Basically it's the electrical engineering equivalent of http://www.whitetreeaz.com/gibber/faeri ... _waltz.jpg]this little beauty.

The percussion instructor here is going to see that.

(weird, wouldn't let me post without breaking the link)

low post count

It's an anti-spam measure, post some more and you'll be able to link urls.

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solidxsnake
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### Re: 0730: "Circuit Diagram"

I go to UMass Amherst, and for our circuits problem set in Physics E&M, our prof (an obvious xkcd fan) decided to go ahead and give us the problem: "Use Kirchoff's laws to solve for the current through and voltage drop across all elements in this circuit. For help, email Randall Munroe directly" and gave us this diagram as the circuit. Answers are worth 1 point and are in essay format via MasteringPhysics online submissions.

I wonder how many e-mails from absolutely baffled students Randall will be getting? xD

BrianB
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### Re: "Circuit Diagram" Discussion

jslegers wrote:...So, I too confirmed the resistor blob value of 25265/33783 ohms using MATLAB symbolics and a reduced admittance-matrix [Zeq = (Ynn - (Ynr Yrr^-1 Yrn))^-1]. As mentioned above, this rounds to ~0.7479 ohms. And, while I appreciate the sentiment, It can only be ROUNDED to 1.337 mhos, and that likely happened by accident. Also, I now have an unmitigated desire to form a band called L337 Mhos.

You would likely not be interested to know that, for 5% normally-distributed resistors, this equivalent resistance would be ~ 0.7479 +- 0.0065 ohms. For 1% resistors, it would be +-0.0013 ohms. This comes from simulation in MATLAB.

Just thought I'd weigh in.

Your logic is flawed, since 5% resistors do not have a normal distribution. They have a big "hole" from -2% to +2%, as that is where 2%, 1% and .1% resistors are taken from.

PhoReaper
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### Re: 0730: "Circuit Diagram"

What's the symbol next to 3 Liters? It looks like some kind of capacitor, but I'm not sure if it's one I don't know, or one that's made up, since it's ages since I've done any electronics.

phlip
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### Re: 0730: "Circuit Diagram"

It's semi-made-up, I think... a similar symbol with a straight line and just one of the two curvy lines is a polarised capacitor... having two of them like that I guess would mean having two polarised capacitors in series, with opposite orientations, as a single unit. Which wouldn't be particularly useful, as a thing. But then, given it appears to have a capacity (measured in litres) rather than a capacitance, who knows.

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`enum ಠ_ಠ {°□°╰=1, °Д°╰, ಠ益ಠ╰};void ┻━┻︵​╰(ಠ_ಠ ⚠) {exit((int)⚠);}`
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alsimoneau
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### Re: 0730: "Circuit Diagram"

I made a modelica simulation of the resistor mess and I got 0.747861 Ohms.
I'm going to try to solve the equations by hand to try to get a real answer.