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The Big Misconception About Electricity

vil says...

Nah I dont see a bait and switch. I see people thinking electricity goes down wires while the underlying real world is fields propagating through space.

It really is a difference if you have the lightbulb 1 meter away or 1 light second away. We have a tendency to think abstractly of these situations, freely giving things ideal properties that they dont have and taking away the properties we dont like to use in our petty examples.

If you had enough voltage to overcome the drop in "ideal" 1 light second long cables they sure as hell would induce enough current in parallel cables 1 m away to light a bulb :-)

All that said people do under-appreciate how fast the speed of light is, just as they under appreciate how much a billion of anything, especially money, is.

The speed of light is getting to your destination instantly from your own point of view.

The Big Misconception About Electricity

bcglorf says...

This is also a trick question, and in a way that I kinda dislike because it additionally confuses matters by the setup.

Specifically, any change to the electrical field in the wire triggered by something like flipping the switch IS always limited to propagating at the speed of light, and as such WILL take 1s to travel the ~300,000km through the wire.

There's a bait and switch here though, were if the wires are close enough, and the power on the wire is high enough, there is a strong enough magnetic field in the wire to reach across the 1m distance to the end of the wire by the light bulb. That magnetic field will induce a very small electric field on the wire as well. Calling that 'lighting' the bulb though is 100% a trick question though as no existing light bulbs are sensitive enough to light up from that little current unless the 'live' side of the wire is both in very close proximity and running very high voltage.

The part I dislike, is too many people believe that electricity running in a cable is 'faster' than light, and the trick here kinda re-inforces that rather than helping to clear that up for people.

Mordhaus (Member Profile)

Perhaps the weakest link in the US electrical system

spawnflagger says...

this guy covers interesting topics, but is really longwinded. I wish someone would make a "digest" version of his videos... I bet this 25 minutes video could be cut into 5 minutes.

also for near the end (not sure which prior video he was defending) - it's not the voltage that kills, it's the current. And is why GFCI trips on a few mA.

UK and EU also have power strips, but 220+ Volt systems need half the current to get same power, so overloading those wires is less likely.

I've seen a UK power strip that failed and actually shorted hot to ground/earth (fuse didn't help), and a TV was plugged into it, so energized the satellite TV coax cable's ground, which fried the expensive distribution equipment in the wiring closet (which must not have been properly grounded either).

James May's Tesla Model S has failed!

spawnflagger says...

I have another suggestion - if the computer is on, check the charge level of the 12V battery, and turn on the the system to charge it occasionally... Just drain the big high-voltage battery a tiny bit, what's the big deal?

Back-To-School Essentials | Sandy Hook Promise

harlequinn says...

The document is in duplicate. Literally in the link. Yes, fingerprint card also. The cost is low. The cost of the firearm is a separate issue.

Yes, the background check. The "process" I'm referring to has context, i.e. the background check process. Obvious really.

"No one asked you that."

You asked me.

"So [do] you think machine guns aren't firearms...or do you think they aren't really illegal? Edit: What about bazookas, grenades, mortars, etc.?"

"Which you begrudgingly".

What language made it begrudging? I stated it was the case without any issue. Stop making stuff up.

I didn't say they can't be regulated. I said that they can't be "effectively regulated". I also stated that there are many regulations that are probably illegal (waiting for supreme court challenges). And I said that there are some regulations that do exist because the supreme court debated it and came to the conclusion that it was within the scope of the 2A.

"especially when you can verify by just scrolling up"

Yeah, exactly, so what are you on about. My comments are literally above you. Why distort them? Do you have comprehension issues? No shame if you do.

"This is a paranoid delusion."
You're entitled to your opinion. History supports their argument though.

"Your argument was there are better issues to throw money at, bucketloads you said, now you admit it takes no money and declare yourself correct"

Yes, there are better issues to throw money at, but the issue is they don't want to throw money at anything when there is a low cost red herring issue they can use to gain public standing instead.

"Then don't be dumb and fuck little kids.
Don't be dumb and rape random women.
Don't be dumb by getting caught in the Jr high locker room filming.
Don't be a snarky tool who hides from what he said by doing mental gymnastics to pretend their warnings aren't implications.
See how giving these warnings imply you needed warning? That's how warnings work."

Yes, they are all warnings. And valid ones at that. The issue is context. You don't put a "warning strong current" warning in the middle of a desert because there is nothing to warn about.

Likewise making those warnings here makes no sense. Ergo, no, these warnings don't imply anyone needs warning. They are just random warnings.

Otherwise we could continue on and I could say:

Don't be dumb and fuck your mother's dead body.
Don't be dumb and fuck animals.
Etc., etc., warnings that are truly good advice but make no sense in the given situation.

On the other hand:
"Danger, high voltage wires" on a cabinet that holds a large transformer makes sense.
"Do not dig, high pressure gas lines buried here" above buried high pressure pipes makes sense.

Do you see the difference?

"Everyone is welcome, welcome to post as much or little as they choose"

Well, everyone is welcome until they're not. And they're not welcome pretty quick here.

"but if I see lies, misstatements, abuse, or insults when none are called for, I'm going to say something, just like I do in person"

Funny about that, that's what I'm doing.

newtboy said:

Not in my experience. I've known many people who tried in Texas and Nevada, all failed. They said it was about 3 pages in triplicate (4 with cover page, totalling 12), fingerprints, photos, a pristine criminal record, chests of cash (the guns cost thousands or tens of thousands), a Class 3 FFL dealer willing to sell to you, 9 months to a year waiting for approval, and no local ordinance against it (local police will be notified).

I said the background check is similarly difficult to pass, not the entire process.

No one asked you that. We balked at your claim-
"The 2A specifically says "arms". There is plenty of debate and case law regarding what arms they meant. Suffice to say there isn't a shadow of a doubt that it means firearms (long and short) of all varieties commonly available."
...and I then gave you the federal definition of "firearms" which you begrudgingly admitted trumps yours, but still cling to the concept that firearms can't be regulated (even though they clearly are). I'm surprised you recall it so differently, especially when you can verify by just scrolling up.

This is a paranoid delusion. Because that's a possibility in a future where the 2a is repealed, they think that's enough reason to ignore any positive uses, like knowing if the person just diagnosed with schizophrenia has an arsenal, or the person who's stalking your 15 year old daughter, or the man who beats his wife. Also, taken to conclusion, that argument is basically "It might make it harder for me to break the law. That's unacceptable." Hardly a reasonable argument imo.

? Your argument was there are better issues to throw money at, bucketloads you said, now you admit it takes no money and declare yourself correct?!

Then don't be dumb and fuck little kids.
Don't be dumb and rape random women.
Don't be dumb by getting caught in the Jr high locker room filming.
Don't be a snarky tool who hides from what he said by doing mental gymnastics to pretend their warnings aren't implications.
See how giving these warnings imply you needed warning? That's how warnings work.

Because I post here doesn't make me the big dog...I'm not even top 20. Everyone is welcome, welcome to post as much or little as they choose, but if I see lies, misstatements, abuse, or insults when none are called for, I'm going to say something, just like I do in person. That's called being an upright citizen. I guess you prefer those who shrink away from that obligation....so hit ignore. That's what I'm doing.

What's better than a drone? A drone with a FLAMETHROWER!

Payback says...

Saw something like this out of China. They used it to burn off garbage that flew up and wrapped around high voltage lines. Apparently there's a lot of airborne garbage in China.

Squirrel Obstacle Course

StukaFox says...

Squirrels are stupidly determined little fuckers when it comes to nuts.

I used to have a bar fridge out on my patio and one day, I threw a bag of peanuts into it because it seemed like a good idea at the time. Anyway, the next day I came out onto the patio and the fridge door was open and the nuts were gone. The little bastards actually chewed through the soft magnetic strip holding the door closed and managed to get the door open and abscond with my hard-earned nuts.

I got even, 'tho -- kinda.

On the corner of our block, we had this big green thing that was a cover for some pretty high voltage stuff underneath. I threw some peanuts under the gap between the cover and the ground and waited. Sure's shit, here comes one cocky fucking squirrel lookin' to score my nuts. Under the cover he goes then --FLASH!! -- BOOM!! -- victory over squirrels! Only he took the power out for the entire block and the surge fried my brand-new Pentium Pro computer. Oh, and one of my neighbors narced me off to PG&E who were none-too-happy with my brilliantly-laid trap and my erstwhile vengeance over genus Sciurus.

I know a lot of people would ask me, "Well, what did you learn from all this?", to which I'd reply, "Not a damned thing."

A Brilliant Analysis of Solar Energy into the Future

newtboy says...

I agree for the most part, but with batteries, now becoming reasonable in size and price, it's not so hard to be totally off grid. Micro hydro can also be efficient power storage if properly designed with a dual reservoir system.
Granted, that seems to work best in small scale setups so far, but there is an island .....(https://www.npr.org/sections/parallels/2014/09/17/349223674/tiny-spanish-island-nears-its-goal-100-percent-renewable-energy)
...currently (since 2014) using this tech to be nearly 100% green.

Dismissing projections as unrealistic without fully examining them may doom our economy and planet.
That's what happened with solar, people just claimed it's expensive and unreliable, which meant those they convinced didn't know how wrong that is, and didn't buy systems or support solar farms. I ignored them and did some light math, and found that even an expensive high tech system with batteries, professionally installed, would pay for itself in about 8 years, with a 20 year expected lifespan (and I live in Humboldt county, with the foggiest airport in America, not Arizona). I'm damn glad I didn't listen. Even a 2 year delay would have cost me 1/2 my rebates, making the system take an extra 2+ years to pay for itself by costing me thousands upon thousands of dollars (instead of saving me thousands per year).

Edit: Also, here in Humboldt we just switched to choice in electricity, we can choose regular pge power (mostly old school generation), a mixture of up to 75% (I think, maybe higher) renewable for cheaper, or 100% renewable for more. All 3 now bill transmission (including voltage/frequency regulation) separately, so it's easy to see what generation alone costs. It's clear so far that mostly renewable is the best bet economically, and I assume it will become more renewable as new technologies become available.....at least I hope so.

A Brilliant Analysis of Solar Energy into the Future

drradon says...

Hardly a brilliant analysis - more like a brilliant piece of advocacy that, like most of its kind, is long on optimistic projections and very short on real numbers and a real analysis of those numbers. For instance: what is the megawatt hour cost of a solar power generation station that can replicate the power responsiveness and availability factor of a fossil power generation station (over a similar life cycle). He quotes the kwh cost for solar and wind power systems but each and every one of them is "backed up" by a much larger conventional power generation system that, ultimately, is burdened with the costs of maintaining grid stability, grid voltage, and grid frequency. There are huge engineering problems and substantial costs associated with maintaining a power supply that we now require to operate a modern economy. Just ONCE, I would like to see the green power advocates address those challenges and costs in a realistic way instead of glossing over them with their fantasy projections.
And I will say, as an aside, that I have spent my entire working career working in the renewable energy sector and fully agree that we need to transition to a renewable energy economy - but unrealistic projections are going to doom our economy if they are taken as being possible in the near term.

Vox: Why America still uses Fahrenheit

ChaosEngine says...

The road and electricity don't matter nearly as much as the metric system because they are geographically bound.

Generally, you drive in one country at a time, and most countries with land borders drive on the same side of the road.

With electrical appliances, they usually stay in one country and the ones that do travel (i.e. laptops, phones, etc) generally will accept any voltage.

mxxcon said:

When it comes to these things I want 3 things to happen in my lifetime:
* US to switch to metric system.
* The world to agree on common household electricity voltage.
* The world to drive on the same side of the road.

Vox: Why America still uses Fahrenheit

mxxcon says...

When it comes to these things I want 3 things to happen in my lifetime:
* US to switch to metric system.
* The world to agree on common household electricity voltage.
* The world to drive on the same side of the road.

Neuroscientist Explains 1 Concept in 5 Levels of Difficulty

dubious says...

It is binary at one stage of processing. when a neuron has enough input it fires an action potential which is a binary one or zero. that then gets "read" by the synaptic terminal and turns back into an analog signal to a "post synaptic" neuron.
As you said, how this signal is then processed by the next neuron depends on a lot of factors including the effects of other neurons. Synaptic strength refers to the amount of electricity the post synaptic neuron sees given this binary 1 or 0 and is often measured at rest. However, if other neurons are firing it can go up or down, amplifying or shrinking it by activating other voltage sensitive ion channels or by increasing the conductance across the lipid bilayer of the cell so that the electricity leaks out of the dendrite of the neuron before it is processed at the soma (the cell body where a new action potential can be generated)

Ickster said:

Hey, dubious. I don't know nearly as much about the details as you do, but I was skeptical when he made the claim to the grad student that inter-neuron transmission was binary. My layman's understanding is that there's a sort of "signal strength" between neurons that can decay or be amplified depending on how those pathways get used. Each signal affects others, and so on--it's much more a very complex feedback system utterly different than the binary instruction pathways used by our current computers.

Newly engineered water superglue

newtboy says...

Perhaps I misunderstood, but I thought it was simply transmitting electricity, not creating it. I was thinking it would work as a sensor where, when it's stretched passed the limit, it will no longer have continuity and could sound an alert.
If I'm wrong and it does MAKE voltage, then yes, synthetic muscles for anything really, not just prosthetics, but androids, underwater machines, etc.

Payback said:

Anything that can create voltage through movement should be able to create movement through voltage, unless it's a chemical process. I'm thinking of synthetic muscles for prosthetics.

Newly engineered water superglue

Payback says...

Anything that can create voltage through movement should be able to create movement through voltage, unless it's a chemical process. I'm thinking of synthetic muscles for prosthetics.

newtboy said:

It seems like high quality industrial silicone.
The ionic version was awesome, and could make a stretch great sensor.



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