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I put a toaster in the dishwasher (2012)

jdstillwater.blogspot.com

291–300 of 331 posts

Re: I put a toaster in the dishwasher (2012)

#291
post #164

It is because people use heuristics to navigate their lives. Instead of doing complicated engineering reasoning all the time to ensure their safety they learn simple “rules of thumb”. These rules are incorrect in as much as they have both false positives (something which the rule prohibits, but is safe) and false negatives (something which the rule lets you do, but is not safe). I’m a hobby jeweler and I use an ordin…

I think the social friction from getting all of this right/wrong really damages inquisitive minds. The visceral negative response you get from, "Wait, I don't think that's right, it's more complicated than that", helps prevent speaking up the next time, unless you have an inherently disagreeable personality (which I cherish working with). I see it all the time with kids. They'll see some fundamental truth that takes…

I've come to realize that pretty much every general rule we have is only ever really true within a bounded context defined by a certain set of assumptions, and models that we think are universally applicable seem so simply because we can't (yet) look beyond their context of applicability.

Even scientific models that we regard as describing fundamental laws of nature will stop describing reality accurately once you hit extreme conditions -- Newtonian physics breaks once you're dealing with relativistic contexts, for example.

The human mind has tendency to generalize its heuristics, and hold certain rules to be either absolutely true or absolutely untrue, which unfortunately hobbles our ability to use our rationality to its fullest potential. People will often dismiss an entire model as being universally "false" as soon as they see a single data point that it doesn't work for, and then try to formulate a new model that's still trying to encompass everything, everywhere. Maybe we'd do better to interpret falsifying data points as helping to map the outer boundaries of the model's applicability, and formulate multiple models, each optimized for different contexts, and each regarded as valid within its bounds.

Re: I put a toaster in the dishwasher (2012)

#292

It is because people use heuristics to navigate their lives. Instead of doing complicated engineering reasoning all the time to ensure their safety they learn simple “rules of thumb”. These rules are incorrect in as much as they have both false positives (something which the rule prohibits, but is safe) and false negatives (something which the rule lets you do, but is not safe). I’m a hobby jeweler and I use an ordin…

"No metal in the microwave" is good general-purpose advice but a reasonable person might notice that the microwave interior is basically all metal so there must be more to that advice than meets the eye.[0]

[0] Microwaves also contain transformers.

Re: I put a toaster in the dishwasher (2012)

#293
post #118

Earlier quoted context omitted.

oh, yeah, i don't think an electric showerhead in my house would work very well at all; some dumbfuck wired it with 15-gauge wire (1.4mm diameter, safe for up to about 10 amps) and at 240 volts you need more like 40 amps to provide a comfortable shower, depending on water flow rate the entire house is on a single anemic 25-amp circuit breaker. at a low-flow 6 liters per minute (100g/s) heating from 15° to 40° (Δ temp…

>on the other hand, if you're building an apartment building in brazil or a hotel in costa rica, there's nothing stopping you from including an 80-amp circuit in every bathroom for the electric shower. Do these countries not have any limit on the current in a circuit? Over here we're not allowed more than 16A in residential use and that's over 2.5 mm^2 wires. What kind of conductors do they use in Brasil for 80A circ…

i'm not familiar with brazilian regulations but normally 80 amps would be about 3-gauge, 26mm². you can bend it with your bare hands if you get the stranded stuff. here in argentina people are evidently a lot more lax than that, so maybe in brazil they are too, but clearly you need at least 12mm²

Re: I put a toaster in the dishwasher (2012)

#294

It is because people use heuristics to navigate their lives. Instead of doing complicated engineering reasoning all the time to ensure their safety they learn simple “rules of thumb”. These rules are incorrect in as much as they have both false positives (something which the rule prohibits, but is safe) and false negatives (something which the rule lets you do, but is not safe). I’m a hobby jeweler and I use an ordin…

Just had this exact discussion with the kids at dinner yesterday. In our case, we talked about the simplified traffic light rule “go on green, stop on red“. This to come up is wrong, of course. Because if the light turns red while you are crossing, stopping would be the worst thing you could do.

Re: I put a toaster in the dishwasher (2012)

#295

Earlier quoted context omitted.

Electricity takes the path of least resistance. If things are done right, that means through the metal heating element and the ground wire, and not through your body.

This is a dangerous myth. Electricity takes all available paths, with less current flowing through the paths with greater resistance. As far as I understand, the main reason people don’t get electrocuted even with improperly grounded shower head heaters is that (as noted in the post), tap water is generally not very conductive in the first place, so you’ve effectively got a gigantic resistor between you and the wires…

It's not a myth. Your second paragraph basically agrees with me and contradicts itself.

so you’ve effectively got a gigantic resistor between you and the wires (assuming there’s a continuous path through the water at all). So even if the least resistance path is through you, the amount of current will be tiny due to Ohm’s law.

That is, by definition, NOT the "least resistance path".

Re: I put a toaster in the dishwasher (2012)

#296
post #103

Earlier quoted context omitted.

no, electric showers heat the water much more effectively, providing way more comfort; here in argentina i have to wait 45 seconds or so for the shower to stop running cold because the hot water has to run all the way from the hot-water tank in the kitchen. and i have to cut the shower short after about 20 minutes because i run out of hot water. i had the same two problems when i lived in the usa, though constant-rec…

I had one of these in an outside room as a teenager and in the winter it was terrible: You can only heat water so much for the available wattage and when it was cold the water was so cold that only a thin trickle could be heated to a comfortable showering temperature.

i admit i've only used them in countries that don't really have winter, where they were great. except the time i got shocked

Re: I put a toaster in the dishwasher (2012)

#297
post #164

It is because people use heuristics to navigate their lives. Instead of doing complicated engineering reasoning all the time to ensure their safety they learn simple “rules of thumb”. These rules are incorrect in as much as they have both false positives (something which the rule prohibits, but is safe) and false negatives (something which the rule lets you do, but is not safe). I’m a hobby jeweler and I use an ordin…

I think the social friction from getting all of this right/wrong really damages inquisitive minds. The visceral negative response you get from, "Wait, I don't think that's right, it's more complicated than that", helps prevent speaking up the next time, unless you have an inherently disagreeable personality (which I cherish working with). I see it all the time with kids. They'll see some fundamental truth that takes…

I still remember lots of microwaves coming with metal racks so you could stack multiple things in them. Sometimes they still do come with them.

https://www.youtube.com/watch?v=14oO_saaM9Q

Re: I put a toaster in the dishwasher (2012)

#298
post #294

It is because people use heuristics to navigate their lives. Instead of doing complicated engineering reasoning all the time to ensure their safety they learn simple “rules of thumb”. These rules are incorrect in as much as they have both false positives (something which the rule prohibits, but is safe) and false negatives (something which the rule lets you do, but is not safe). I’m a hobby jeweler and I use an ordin…

Just had this exact discussion with the kids at dinner yesterday. In our case, we talked about the simplified traffic light rule “go on green, stop on red“. This to come up is wrong, of course. Because if the light turns red while you are crossing, stopping would be the worst thing you could do.

Also, just because the light is green does not mean it is safe to go. You should still look and make sure the other traffic is actually coming to a stop.

Re: I put a toaster in the dishwasher (2012)

#299

Earlier quoted context omitted.

It's quite impressive it kept working for that long, and even more amazing someone was capable of saying "no, let's not cut the power, there might be a problem if we do"

It is only impressive coming from the consumer grade electronics. Microchips, capacitors, PCB's and other stuff like manufactured for defence have much wider and higher tolerances. One won't find the cutting edge 2 nm processes (depending on the specific area of defence, 200-300 µm would still be cutting edge today for them), materials used are different, plus all sorts of chemical and physical hardening is employed.…

> 200-300 µm would still be cutting edge today for them

Sorry, I think you're off by a few orders of magnitude, do you mean 200-300nm?

Re: I put a toaster in the dishwasher (2012)

#300
I am not educated in the US and never used toaster before entering the US, and I am surprised so many people think toasters can't be washed. Most electronic and electric products can be dried if you leave it there for a long enough time. I washed many of them throughout my life.
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