Everyone knows that the path of least resistance is the path that will always be taken, be it by water, electricity or the feet of humans. This is where the PCB presented by [ElectrArc240] on YouTube is rather confusing, as it demonstrates two similarly sized traces, one of which is much shorter than the other, yet the current opts to travel via the much longer trace. If you were to measure this PCB between each path, the shorter path has the lowest resistance at 0.44 Ω while the longer path is 1.44 Ω. Did the laws of physics break down here?
Of course, this is just a trick question, as the effective resistance for an electrical circuit isn’t just about ohmic resistance. Instead the relevant phrasing here is ‘path of least impedance‘, which is excellently demonstrated here using this PCB. Note that its return path sneaks on the back side along the same path as the long path on the front. To this is added a 1 MHz high current source that demonstrates the impact of alternating current, with reactance combining with the resistance.
Although for direct current it’s fair to say that impedance is the equivalent of resistance, once the inductance of a trace has to be taken into account – as in the case of AC and high-frequency signaling – the much higher inductance of the short path means that now the long path is actually the shortest.
When you are doing some impedance matching in your favorite EDA software while implementing an Ethernet RMII link or similar, this is basically part of the process, with higher frequencies requiring ever more stringent mechanisms to keep both sides happy. At some point any stray signals from nearby traces and components become a factor, never mind the properties of the PCB material.
Electricity takes ALL paths, it’s just that some allow exponentially more electrons to flow than others. If you had sensitive enough multimeter and noise floor comparable with liquid helium, you could connect LED to a CR2032 in Japan and detect single electrons in Spain. It’s simple dynamic systems, laplace equations etc.
Perhaps it’s clear to you, but how does the electron get from Japan to Spain? What are you saying here?
Magnetics
Oh nose! A coil with enough henry has almost infinite resistance to HF power? Who would’ve thought HF “ELECTRICITY” doesn’t take a path of negligible resistance to DC.
I mean this if FUNCKIN HaD and nobody here as ever heard of any type of RF HF antenna… /S
Aren’t many WiFi Antennas “just” short circuits? Make a fluff video about that and get on HaD
Please – don’t put this ClickBait shit on HaD (specifically the title of that YT-vid – not sure about the content, only watched a little).
Okay, let’s try again (hopefully correct formatting this time):
No it isn’t. Not confusing and no trick question, just pure 100% unadulterated CLICKBAIT (garbage).
The electricity is still taking the path of least resistance TO IT!
Oh nose! A coil with enough henry has almost infinite resistance to HF power? Who would’ve thought HF “ELECTRICITY” doesn’t take a path of negligible resistance to DC.
I mean this if FUNCKIN HaD and nobody here as ever heard of any type of RF HF antenna… /S
Aren’t many WiFi Antennas “just” short circuits? Make a fluff video about that and get on HaD
Please – don’t put this ClickBait shit on HaD (specifically the title of that YT-vid – not sure about the content, only watched a little).