I invite you to touch an electric fence with a stick then.
You’re describing my pre-internet childhood.
(It wasn’t a 10k volt t-rex fence though)
With your stick?
I’ve installed a few, and you do have to test them somehow.
Best way is a long piece of grass, hold it about 30cm down and touch the other end to the fence. Most you get is a little tingle
i’m not touching your stick man, gross!
Oh yeah everyone knows electricity .
It looks so easy, and it is easy, but then it kills you.
Anything conducts electricity if there is enough of it.
IIRC, he was messing with the kids and knew it was off because the lights were off. He proceeded to put his hands on it and convulse wildly as a joke.
He was messing with the kids when he grabbed the wires, not when he threw the stick.
I always saw it as being part of messing with the kids, he looks at the warning lights on top of the fence first. And for my headcannon at least, Grant is savvy enough to know that’s no way to test if the fence is live or not, lol.
Selling the bit is important too
As a PhD who has tried doing home improvement projects, it’s the most believable thing in the film.
Some pleeb shouted at me, “I thought you were an engineer!” And I shouted back, “A software engineer!” while I hammer a nail with my shoe.
Ah, a C programmer.
I’m a regular engineer and yeah I pull such shit. Listen, there’s a reason I tell everyone not to do what I do.
The difference between a regular idiot doing a dangerous job and an engineer doing a dangerous job is the engineer knows which parts of the job he’s risking imminent death on. There may often be no other difference.
When it comes to an engineer doing a dangerous job in a domain other than his or her own, I would say that all the engineer knows is how bad things can be fucked up when one is trying to do expert stuff outside one’s own domain, because they’ve been in a position were they were the experts and some non-expert was saying things and trying stuff for their expert domain.
After seeing others do it in one’s own expert domain one generally realizes that “maybe, just maybe, that’s exactly how I look outside my domain of expertise to the experts of that domain when I open my big fat mouth”.
Really?
Genuinely asking, I’m just an engineer… with very very bad grades. Passed was enough for me.
Once a professor asked me if I wanted to take the exam again because it was clear that I knew more than what I showed on the exam (a lot of 2 + 2 = 5 mistakes, I was fairly good at that and owe most of my low grades to that). I asked him if I passed, he said yes. Fuck that shit, I’m taking that grade and parading it across town, wooohoo 🥳.
As they say, a PhD is about learning more and more about less and less. Some of the smartest people at conferences I’ve attended legitimately risk death crossing the street.
Lol 😂, reminds me of some of the professors at uni 😂.
Actually some of the most naïve people I’ve ever met were theretofore academically successful.
My fiancee has a couple degrees while I just graduated high school. She’s incredibly smart but I’m definitely more street savvy. She grew up a bit sheltered.
Is his PhD in Electrical Engineering?
Why people gotta hate on a movie three decades old that remains perfect?
Gotta meme to keep it alive
A PhD wouldn’t know anything about science, so its pretty accurate really :/
You realize you can have a PhD… in science? (Any specific kind of science you wanna pick.)
You can get a philosophy doctorate in science? Honestly no, I didn’t realize that at all
The trick lies in philosophy coming from Greek philosophia which is love for/love of wisdom. It never referred to what we understand as philosophy, but rather affinity for studying.
He probably wanted to prevent significant arcing by using a higher impedance test apparatus due to the high voltage.
not a phd in physics huh
Idiot didnt know the MAD was 2’2", SMDH.
Clearly his PhD is not in electrical engineering or biology
It’s actually a PhD in trombone. Someone misheard it one time, and nobody has ever thought to follow up.
“Oh, Alan? Yeah, he has a doctorate in bones or something.”
His job is beach
Hey it’s a “It’s a UNIX system” movie, isn’t it?
The funny thing about that quote is that it really was a Unix system that was shown on screen.
What was the name of the 3D file manager again?
It had a wonderfully bizarre name: fsn
Did you know the weird 3d file system navigation thingy was a real program (just not widely used)?
But I can’t get over the way she held the mouse lol
I know that!
Even throwing a metal pipe against it won’t do anything. Electric fences have one electrode in the ground, and that’s how your body makes the circuit. If they had run and jumped onto the fence, then jumped off on the other side they would have been fine with the fences still active.
Source: I’ve set up an electric fence and been shocked multiple times, once through my head.
You’re assuming the dinosaur fence operates on the same principal as a regular livestock electric fence. I put it to you that the Dino enclosures use alternating positive and negative stringer wires, where touching one won’t do anything, but touching two will make a short circuit.
That would make a lot of sense, but as we can see the stringers are connected together, meaning they’d just short out if they were alternate polarities. To me this indicates that it’s like a standard livestock fence, with an electrode in the ground somewhere and the circuit completing through the animal.
However, considering my 16’x48’ pig enclosure required a three-foot rod to be grounded, a system large enough for a sauropod would need a lot of grounding. Considering this, the fact that they used a circuit-through-animal design indicates it probably wasn’t the best way to do it.
Spared no expense…
Maybe the stringer spacers are polymer though. Like those separation bars you see on residential power lines
Maybe they’re polymer but they look pretty metallic and there’s an awful lot of them. Plus if the stringers are under enough tension for a full grown man to climb them they wouldn’t need separators.
uhm, I’ve seen (touched, oops) electric fences (low power tho) with both conductors in the wire, uncovered but not touching.
Yet Tim gets shocked when hanging on the fence when it turns on while he’s climbing down. I trust movie science far more than your acquired knowledge. Your ignorance is probably what’s holding you back from full blown deity.
Ever seen birds standing on powerlines?
As a non-technical person, can someone explain to me why this is bad? I thought wood isn’t a good conductor?
How good of a conductor wood is depends on its state. If it is very dry and not salty, this should be safe (although he could have taken the piece of wood more at the end to increase the distance between him and the fence and the length=isolation through the piece of wood). If it is wet and salty, it might be dangerous.
There was a major storm just a few hours before this, so the wood is likely wet. However, he threw it against the fence; he wasn’t touching it when it made contact with the wires.
Yeah. Therefore the wood won’t do anything.
The higher the voltage, the less the electricity cares how good a conductor something is. Air is a shitty conductor, and yet, lightning doesn’t give a shit.
Well, I have an EE Degree specialized in Digital Systems - pretty much the opposite side of Electronic Engineering from the High Power side - and I would be almost as clueless as that guy when it comes to testing a 10,000V fence for power.
On the other hand I do know a lot of interesting things about CPU design ;)
What’s the most interesting thing you could tell us about CPU design, something that a layman could appreciate.
You should know as a software developer I write inefficient code and appreciate all the extra clock cycles we get these days haha.
First a fair warning: I learned this stuff 3 decades ago and I’ve actually been working as a programmer since then. I do believe the example I’ll provide still applies up to a point, though CPUs often implement strategies to make this less of a problem.
=====
CPU’s are internally like an assembly line or a processing pipeline, were the processing of an assembly instruction is broken down into a number of steps. A rough example (representative but not exactly for any specific CPU architecture) would be:
- Step 1: fetch assembly instruction from memory
- Step 2: fetch from into the CPU data in memory that the instruction requires (if applicable).
- Step 3: execute arithmetic or binary operation (if applicable).
- Step 4: evaluate conditions (if applicable)
- Step 5: write results to memory (if applicable)
Now, if the CPU was waiting for all the steps to be over for the processing of an assembly opcode before starting processing of the next, that would be quite a waste since for most of the time the functionality in there would be available for use but not being used (in my example, the Arithmetic Processing Unit, which is what’s used in step #3, would not be used during the time when the other steps were being done).
So what they did was get CPUs to process multiple opcodes in parallel, so in my example pipeline you would have on opcode on stage #1, another that already did stage #1 and is on stage #2 and so on, hence why I also called it an assembly line: at each step a “worker” is doing some work on the “product” and then passing it to the next “worker” which does something else on it and they’re all working at the same time doing their thing, only each doing their bit for a different assembly instruction.
The problem with that technique is: what happens if you have an opcode which is a conditional jump (i.e. start processing from another point in memory if a condition is valid: which is necessary to have to implement things like a “for” or “while” loop or jumping over of a block of code in an “if” condition fails)?
Remember, in the my example pipeline the point at which the CPU finally figures out if it should jump or not is almost at the end of the pipeline (step #4), so everything before that in the pipeline might be wrong assembly instructions being processed because, say, the CPU assumed “no-jump” and kept picking up assembly instructions from the memory positions after that conditional-jump instruction but it turns out it does have to jump so it was supposed to be processing instructions from somewhere else in memory.
The original naive way to handle this problem was to not process any assembly instructions after a conditional jump opcode had been loaded in step #1 and take the processing of the conditional jump through each step of the pipeline until the CPU figured out if the jump should occur or not, by which point the CPU would then start loading opcodes from the correct memory position. This of course meant every time a conditional jump appeared the CPU would get a lot slower whilst processing it.
Later, the solution was to do speculative processing: the CPU tried to guess if it would the condition would be true (i.e. jump) or false (not jump) and load and start processing the instructions from the memory position matching that assumption. If it turned out the guess was wrong, all the contents of the pipeline behind that conditional jump instruction would be thrown out. This is part of the reason why the pipeline is organised in such a way that the result of the work only ever gets written to memory at the last step - if it turns out it was working in the wrong instructions, it just doesn’t do the last step for those wrong instructions. This is in average twice as fast as the naive solution (and better guessing makes it faster still) but it still slowed down the CPU every time a conditional jump appeared.
Even later the solution was to do the processing of both branches (i.e. “jump” and “no-jump”) in parallel and then once the condition had been evaluated throw out the processing for the wrong branch and keep doing the other one. This solved the speed problem but at the cost of having double of everything, plus had some other implications on things such as memory caching (which I’m not going to go into here as that’s a whole other Rabbit Hole)
Whilst I believe modern CPUs of the kind used in PCs don’t have this problem (and probably also at least ARM7 and above), I’ve actually been doing some Shader programming of late (both Computing and Graphics Shaders) and if I interpreted what I read correctly a version of this kind of problem still affected GPUs not that long ago (probably because GPUs work by having massive numbers of processing units which work in parallel, so by necessity they are simple) though I believe nowadays it’s not as inadvisable to use “if” when programming shaders.
Anyways, from a programming point of view, this is the reason why C compilers have an optimization option of doing something called “loop unrolling” - if you have a “for” loop with a fixed number of iterations known at compile time - for example
for(int i = 0; i < 5; i++){ /* do stuff */ }
- the compiler instead of generating in assembly a single block of code with the contents of the “for” loop and a conditional jump at the end, will instead “unroll the loop” by generating the assembly for the body of the loop as many times as the loop would loop - so in my example the contents of that “for” loop would end up as 5 blocks in assembly each containing the assembly for the contents, one after the other, the first fori=0
, the next fori=1
and so on.As I said, it’s been a long time since I’ve learned this and I believe nowadays general CPUs implement strategies to make this a non-problem, but if you’re programming microcontrollers or doing stuff like Compute Shaders to run on GPUs, I believe you it’s actually the kind you have to take in account if you want max performance.
Ah ah ah…
You didn’t say the magic word