Most physicists I've met would just use a 5.6 ohm resistor, or whatever they have on hand within an order of magnitude 😅
Use 2 E192 in parallel: a 6.19Ω resistor with a 4500Ω resistor. This gives 6.1846Ω which is close enough for rock and roll.
E192 resistors are expensive. E6 resistors 6.8Ω and 68Ω in parallel, available pretty much everywhere components are sold, result in 6.1818 Ω, which is within 0.05 % of the target, around the edge of what you can achieve without active temperature compensation.
This guy electrons!!! <3
well there's certainly none in the chip aisle
This is EXACTLY how it went for me when I moved from a Physics to an Electronics Engineering degree at University.
Also, the trying to understand how the various circuits worked from the point of view of "electrons moving" was a hard to overcome early tendency (even simple things like LC circuits, for example, are only really understandable as ressonant stable states and for complex circuits you really have to go higher levels than "electrons" to be able to understand then in any reasonable amount of time).
On the upside when we got to things like how tunnel effect diodes worked, the whole thing was just obvious because of having had an introduction to Quantum Mechanics in the Physics degree. Also the general stuff about how semiconductor junctions work is a lot more easy to get if you come from Physics.
(In summary: Physics really helps in understanding HOW the various components in Electronics work, but doesn't at all help in understanding how to use them to assemble a complex structure to achieve a given objective. Curiously this also applies to Mathematics and Software Development)
Where are the spherical cows?
would be a great band name
No no no no, I think you got that wrong. Chickens are spherical, cows on the other hand are cuboid. And humans are cylindrical.
Watching people repair old electronics on Youtube has opened my eyes to the realities of real-world electrical engineering. In short: it's all about tolerances.
A power supply may have a nominal voltage of 5V, but anything from 4.8 to 5.2 is a-okay. Why? Because your TTL components downstream of that can tolerate that. Components that do 5V logic can define logic zero as anything between 0 and 0.8 volts, and logic one as low as 2 volts. That's important since the whole voltage rail can fluctuate a lot when devices use more power, or draw power simultaneously. While you can slap capacitors all over the place to smooth that out, there's still peaks and dips over time.
Meanwhile, some assembly lines have figured out how to aggressively cost-reduce goods by removing whole components from some circuits. Just watch some Big Clive videos. Here, the tendency is to lean heavily into those tolerances and just run parts hot, under/over powered, or just completely outside the published spec because the real-deal can take it (for a while). After all, everything is a resistor if you give it enough voltage, an inductor if the wire's long enough, a capacitor if the board layout is a mess, and a heatsink if it's touching the case.
The way I got 100 in a lab once (electrical engineering) was by not using inductances in a frequency filter because their +/- is shit.
And your LEDs will last a lot longer if you remove one of those two resistors
The humble potentiometer:
The least reliable resistor. Not to mention the trial-and-error getting it close enough to the target value.
They are, however, absolutely thrilled that the smallest resistor package is now ~ 1x the plank length on the narrow side.
Astrophysicists would be happy with a 1 ohm resistor.
You should see their simplified periodic table.
