Episode #1092

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      Question #1: “Sucks”

      • Hello from the UK. I haven’t listened to 1091 so maybe you addressed this but I have to respond to the toilet syphon discussion if only for therapy for me. I wouldn’t be surprised if I am not the only one responding to this! Suck does not exist. After 3 uses of the word I was screaming at the podcast for you to stop. But no, you blithely carried on despite my protestations seemingly taunting me. Humans love to give a name and thus a physicality to an absence of a thing. A classic example is closing curtains at night to keep the cold out. Cold is an absence of heat energy, it can not travel. Sometimes scientist use the absence of a thing such as ‘holes’ (the absence of an electron in semi-conductors) because it makes the math easier. So what is ‘suck’ the absence of — air pressure. So the only force acting on the system is air pressure. Unless your toilet is truly enormous then this pressure is equal on all exposed surfaces. So with this in mind consider a simple U bend. Add water, initially the water oscillates back and forth until turbulence losses cause the water level to equalise on both sides of the U. Where are the forces coming from that cause this oscillation? If the water level is not equal then the column of water on one side weighs more than the other so that side pushes down. Now add a second U, this one is inverted so the two U’s form and S bend, the classic toilet exit shape. Adding extra mass (water) in the trap causes the height and thus weight of the column of water to dominate the system. This pushes water over the second U. If, and only if, you can get enough mass over the second U then you create a column of water on the exit the weighs more than the column of water in the bowl. The weight of this exit column pulls the rest of the water with it and hopeful anything you might have added. Water is incompressible so it isn’t going to stretch and snap in the middle. Regards, Sean.
      • More nuance on audio cable segment Message: Long time patron and listener from near the beginning, love so much what you do. The SGU is the only podcast I MUST listen to every week when it comes out. On the topic of audio cables, I think your analysis was spot on. Something Christian said towards the end though, was also correct, that when it comes to transporting data through cables, other factors become significant, and then the difference between a cheap cable and a more expensive cable can really be important. Adam Savage and friends did some really great work on this. https://youtu.be/AD5aAd8Oy84?si=tI0B0fGQdqiW3UEg Josh Nankivel And I’m a fairly serious hobbyist audio guy and backup sound tech for several venues around town, over the past 40 years of worked with hundreds of pros on concert tours and in studios. Most people who make their living making sure the sound system sounds great in challenging environments buy cable in bulk. Sometimes buying spools of cable and cutting it to length and attaching the appropriate connectors as needed, but also buying lots of stock length instrument, speaker, xlr, speakon, and Ethernet cabling. Everyone has the brands the prefer (it’s never monster cable) but no one is turning their nose up at the monoprice or hosa cables if that’s what there is. If you’re paying much more than $3/ foot for cable you’re a sucker. Matt Monroe

      Quickie with Steve

      https://www.cdc.gov/media/releases/2026/update-on-ebola-outbreak-in-the-democratic-republic-of-the-congo-and-uganda-6-5-2026.html

      Science or Fiction

      Skeptical Quote of the Week.

      ‘Science is a collaborative effort. The combined results of several people working together is often much more effective than could be that of an individual scientist working alone.’ — John Bardeen (the only person in history to be awarded the Nobel Prize in Physics twice)