• ToiletFlushShowerScream@piefed.world
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    2 days ago

    University general chemistry introduced all these wonderful rules the universe followed and everything suddenly made sense and all was right with the world. Then organic chemistry spent class after class explaining how it was all BS and how every rule had so many exceptions that they weren’t actually rules anymore, and the walks back from class were gloomy and sullen.

    • Tollana1234567@lemmy.today
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      21 hours ago

      gen chem was so brutal, many dint pass. or had to retake it. at least not with better than a C. and thats with universities generally lowering the average for each grade so people “can attempt to pass”

    • iocase@lemmy.zip
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      2 days ago

      I went through the same thing with electronics being taught the water model then you’re told to throw that out because AC doesn’t act like water.

      I say bullshit! My instructors didn’t understand AC well enough IMO

      Once you understand AC well enough you realize it still applies to the water model of electrical flow. Induction is inertia, capacitance is pipe deformation from pressure.

      When you slam a valve shut in an old house you make a massive pressure spike (inductive field collapse, flyback voltage spike) which oscillates within a resonant circuit when the pipes absorb that extra pressure by expanding, then releasing that spike back into inertia, which makes a smaller spike back into hoop stress until friction (resistance) saps all of the energy out of the circuit.

      You can make a DC-DC boost converter by opening and closing a valve really quickly on a long pipe and feed the pressure spikes into a check valve.

      • Tlaloc_Temporal@lemmy.ca
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        1 day ago

        Aren’t water flow, electrical flow, and mechanical flow all strictly analogous? As in mathematically equivalent, not just similar?

        • iocase@lemmy.zip
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          1 day ago

          Yeah they are but it seems like most electrical instructors don’t know that they just think “water is close enough as an analogy to electricity but breaks with AC” when in fact they’re both identical. So they’ll tell you to forget the water model while teaching you AC. The inertia/pipe strain comparison is very rare to hear.