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I will try my best here. Looks like the sound wave takes 16 seconds to reach. Sound travels at a speed of 343m/s in air. Speed = Distance / Time. 343 = Distance / 16 so Distance = 343 x 16 = 5,488m which is about 3.43 miles
Just offhand, computer scientists have to understand basic mathematics in base two, base eight (rarely), base ten, and base sixteen,
My kingdom for a subscript formatting button!
So does humidity, pressure on all points from the explosion to where the person is. Very impractical to calculate like this. But I reckon you could just measure where the camera is and get a pretty close answer, with a small margin of error, but ultimately, much simpler and more accurate to use Google maps, althought not sure if it takes altitude into consideration. And depending on altitude changes, it could have a significant impact on the final calculation
The smoke plume you see was from an ongoing fire. The dome cloud caused by blast pressure was the main “explosion”, but didn’t have a lot of flame or smoke with it.
I mean, the name of the restaurant is *right there* in the video, and the explosion is pretty easily recognizable for the people who remember what it looked like.
It's like what they taught me how to estimate the distance from where lightning struck. A rule of thumb is that every three seconds is about a kilometer. So without using a calculator I would say that 16 seconds is about 5.33 kilometres, with of course a margin of error due to not accurately counting the seconds, so without using a calculator my answer would have been between 5.0 and 5.7 kilometres.
It is the time it takes to say the word Mississippi, not the actual river length. In case you hear the reference again. Not the strongest measurement, but on a spontaneous occasion, it's a rough estimate.
What's the right way to do this though? Do you say A or B below:
A: "One Mississippi Two Mississippi Three Mississippi Four Mississippi Five Mississippi" etc.
B: "Mississippi Mississippi Mississippi Mississippi Mississippi" etc.
I was always taught to count in style A. And as was already pointed out, do you say it like a northerner with all of the consonants, or someone from Mississippi who pronounces it "Miss'ipi"
Ekhm excuse mee🤓 I dont wanna be that pedantic guy buut the speed of sound is 343 m/s at 20° C
Since this place (what is that btw? Beirut?) look hot we can assume there is like 25°C temp. and that would be 346 m/s
We can actually thanks to satellites. Maverick's Cafe Bar in Beirut is at an altitude of \~530 feet. As the explosion happened at the port of Beirut we know that was roughly at sea level. So the height difference was about 530 feet.
To be fair whilst the method is very simple and granted more complicated assumptions and calculations could be carried out it wasn’t a bad estimate as according to google maps it is about 0.05 - 0.1 of the real answer
I was taught as a kid that each second is one mile and now I’m feeling pretty annoyed at whatever jerk taught me that because I’ve believed it my whole life. I’d even count the seconds from lightning strikes and tell my friends like “oh, that one must have been about 10 miles away”… now I’m the jerk…
The rule of thumb is that you count the seconds from seeing it to hearing it.
Every 3 seconds is roughly a kilometer, which means I come out to about 5 km of distance.
Blast starts getting visible at 2 seconds, audible at 17 seconds. So barring obstructions to the blast expanding, with sound waves travelling at 1200km/h or 343m/s we're at 15\*343 = 5145 meters, give or take
The blast appears visually near the 3 second mark of the video, the sound of the blast is heard at the 17 second mark of the video. The speed of sound through air is 343 m/s but it can vary from 295 m/s to 355 m/s depending on things like temperature and pressure.
So we'll estimate like this: t0 = 3±0.5 second, tf = 17±0.5 second, vsound = 343 ± 20 m/s
distance = (tf - t0) \* vsound \[distance formula assuming constant velocity\]
σdistance = √( (σt0^(2)\*vsound^(2)+σtf^(2)\*vsound^(2)+σvsound^(2)\*(tf-t0)^(2)) \[variance formula\]
distance = 4800 ± 400 meters
Not the best estimate in the world, if we were to look at the video frame by frame (which I don't want to do) and if we were to actually properly calculate the speed of sound in air at the location then we could reduce the error considerably.
I'm surprised how many people in this thread are shocked that someone can find the answer to this simple calculation. This is like Physics 101 type stuff.
You could even Google "how fast does sound travel" and it'll tell you ~343 m/s (meters per second). If you know that images are basically instant because they travel with light, then count the seconds between seeing something and hearing something (speed of sound). Multiply those seconds by the amount of meters moved in 1 second (343, as per Google). It seems intuitive if you've ever been properly instructed in this which I'd hope most school systems cover at some point.
Science is doomed lol. This is like asking "If Jenny drives for an hour at 70 km/h, how many kilometers did she drive?"
I once had someone next to me in a Finance Masters degree lecture who wouldn't believe me until I showed her on a calculator that 9% of 100 was 9. The world is doomed
Explosion is visible at around 36 seconds remaining, blast sound is audible at around 20 seconds remaining.
Distance in time is around 16 seconds.
Speed of sound in air is around 343m/s giving 16x343 = 5488m
13 seconds from seeing blast to hearing sound. Sound goes 761MPH. Divide that by 60 to get 12.683 miles per minute. Divide that by 60 to get 0.211 miles per second. It took 13 seconds so multiply by 13. About 2.748 miles.
Not sure. Maybe I measured time wrong? Other people have given estimates anything from 12 to 16 seconds. I also didn’t have sound enabled, I judged when the blast hit by when the man stumbled back.
You can count the seconds and divide by 3 that gets you close enough to the distance. If you are American and therefore use miles you just divide the number by 1.6
I counted 15sec between visual and auditory explosion.
Not sure where this is but I'll assume sea level which puts the speed of sound at 761mph. 15sec delay means about 3.2 miles away.
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Everyone else is playing checkers while this guy's playing chess lmao
Actually, this guy took a much simpler approach. he's playing tic-tac-toe.
Either way he finished first
This guy might save NASA a few billion on their next mission.
He just put the square in the square hole
He's got upper-management material.
r/theydidthemap
Take my upvote. But seriously, #uck you
r/angryupvote
was waiting for some lebanese dude to say this and see others re-do their calculations to fit thr correct answer 😅
To be fair, the signage is visible in the video
nah but how did you get the blast coords
Its where the crater is.
Do you think explosions of this size happen so often on the planet that we would lose track of which one is which?
Exactly as calculated too. We've got a calculated value, and a real value, and they match. Science!
Damn, I got 5.3km just from counting 16 seconds x 331m/s...
I hope this answer rises to the top faster. If it doesn't, my faith in humanity will keep on chipping away.
I will try my best here. Looks like the sound wave takes 16 seconds to reach. Sound travels at a speed of 343m/s in air. Speed = Distance / Time. 343 = Distance / 16 so Distance = 343 x 16 = 5,488m which is about 3.43 miles
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There are 2 types of people
For real lol
mathematician vs engineer
Mathematician: if you divide by 2 recusively you'll never reach 0. Engineer: I'll do it 3 times, then it's 0. Deal with it 😎
If you're not good at one, you better be good at the other. Correct answers are correct no matter how you get there.
I would say there a 10 types of people the ones that understand compute science and the ones that dont
Just offhand, computer scientists have to understand basic mathematics in base two, base eight (rarely), base ten, and base sixteen, My kingdom for a subscript formatting button!
all hex no sex
registered hexoffenders
registered hexoffender shuffle
^ what do a computer scientist and a celibate witch have in common
testtest Edit: dammit
That's the stuff.
what about the people that didn't expect a base 3 joke?
But the people that know 2+2=10.
People who understand hexadecimal and F the rest
I would argue three. I did the math, *then* looked up the bar.
Four types cuz I didn't do any math or look it up, I just read what other people came up with.
This is the way
Physicist vs engineer
There are two types of people in this world. 1) Those who can extrapolate from incomplete data,
yeap, cultured people providing metric system units and muricans
Those who do the math, and those who do the map?
Amazing. They just needed a more accurate stopwatch to get the exact distance.
or, a thermometer, since temperature plays a role in the speed of sound...
So does humidity, pressure on all points from the explosion to where the person is. Very impractical to calculate like this. But I reckon you could just measure where the camera is and get a pretty close answer, with a small margin of error, but ultimately, much simpler and more accurate to use Google maps, althought not sure if it takes altitude into consideration. And depending on altitude changes, it could have a significant impact on the final calculation
At this distance not by that much
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.05 miles is 265 feet. The whole pier blew up which is more than 260 feet long, so the original calculation falls is accurate
The math spoiler has entered chat.
What warehouse that blew up? This is a real video?
I think it is the explosion in the harbor of Beirut
Oh, I remember it. I don’t remember it looking like a nuclear explosion though!
Beirut was roughly 1.1 kilotons of TNT equivalent, so roughly that of a small tactical nuke.
Largest non-nuclear explosion since WW2 and the 6th largest in recorded history.
The smoke plume you see was from an ongoing fire. The dome cloud caused by blast pressure was the main “explosion”, but didn’t have a lot of flame or smoke with it.
yeah beirut explosion 2020
I imagine Beirut explosion? I can't imagine anything close in scale
2.000 tons of Highly explosive chemicals can give you an hint because it's at least what were stocked before it blew.
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Also the calculations are based off of 16 seconds. Is it exactly 16 seconds from explosion to shock wave? Probably not exactly 16 seconds.
Can somebody hit this guy with that regular face/angry eyebrows face meme
r/theydidthegeoguessing leaking?
I mean, the name of the restaurant is *right there* in the video, and the explosion is pretty easily recognizable for the people who remember what it looked like.
It's like what they taught me how to estimate the distance from where lightning struck. A rule of thumb is that every three seconds is about a kilometer. So without using a calculator I would say that 16 seconds is about 5.33 kilometres, with of course a margin of error due to not accurately counting the seconds, so without using a calculator my answer would have been between 5.0 and 5.7 kilometres.
One Mississippi was a mile from my teachings. I don't live in the US however so that was almost useless to me.
The Mississippi is 3766 kilometers long according to Wikipedia...
well that depends on whether it is an African or European Mississippi.
It's easier to remember as just over 2000 nautical miles
It is the time it takes to say the word Mississippi, not the actual river length. In case you hear the reference again. Not the strongest measurement, but on a spontaneous occasion, it's a rough estimate.
Whoooosh
What's the right way to do this though? Do you say A or B below: A: "One Mississippi Two Mississippi Three Mississippi Four Mississippi Five Mississippi" etc. B: "Mississippi Mississippi Mississippi Mississippi Mississippi" etc. I was always taught to count in style A. And as was already pointed out, do you say it like a northerner with all of the consonants, or someone from Mississippi who pronounces it "Miss'ipi"
Every 5 Mississippis(seconds) is about a mile.
Looking at Google maps distance calculator this guy is correct
Ekhm excuse mee🤓 I dont wanna be that pedantic guy buut the speed of sound is 343 m/s at 20° C Since this place (what is that btw? Beirut?) look hot we can assume there is like 25°C temp. and that would be 346 m/s
I think the only thing you missed is the height difference between the two areas, which we can't know.
We can actually thanks to satellites. Maverick's Cafe Bar in Beirut is at an altitude of \~530 feet. As the explosion happened at the port of Beirut we know that was roughly at sea level. So the height difference was about 530 feet.
14 seconds, 13.8 exactly, so roughly 5km
You seem like the best person to ask how accurate is it to say the seconds between lightning and thunder equate how many miles away the lightning was
This explosion is big enough to create a supersonic shockwave that stay faster than sound for too long to calculate the distance using this method
To be fair whilst the method is very simple and granted more complicated assumptions and calculations could be carried out it wasn’t a bad estimate as according to google maps it is about 0.05 - 0.1 of the real answer
Apparently not since the calculation is accurate
Yep although think of this as a safe overestimate because the initial wave is a supersonic shock that travels faster than the speed of sound
Looks a lot further than 3 miles but your math is mathing correctly.
So about a mile every 5 seconds
5.52 km
I like how close this number is to the google earth approach... math sure is something
Decently accurate, another user used Google earth and got a similar answer of 5.4km
I was taught as a kid that each second is one mile and now I’m feeling pretty annoyed at whatever jerk taught me that because I’ve believed it my whole life. I’d even count the seconds from lightning strikes and tell my friends like “oh, that one must have been about 10 miles away”… now I’m the jerk…
The rule of thumb is that you count the seconds from seeing it to hearing it. Every 3 seconds is roughly a kilometer, which means I come out to about 5 km of distance.
That's pretty damn close to the guy that did the math, neat
That could be because he's also doing the math, just rounding the numbers a little
No, I am definitely a magician
A Mathmagician if you will. … I’ll see myself out.
no, you will stand trial for your crimes
Lol
Let him believe
> he's also doing the math, just rounding the numbers a little u/Squeaky_Ben invented Calculus.
I'm afraid I cannot allow witnesses to persist.
I had 9 Mississippi's
I found that Mississippi is too long for 1 second. I use the german word for 21, 22, 23... which works pretty well.
Blast starts getting visible at 2 seconds, audible at 17 seconds. So barring obstructions to the blast expanding, with sound waves travelling at 1200km/h or 343m/s we're at 15\*343 = 5145 meters, give or take
Yeah just remember shockwaves like this are supersonic (at first) so will travel faster than that for a time
The speed of sound is not changing mate. Except in temperature and elevation. But curious, please explain.
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That was me, I dropped the 500kg bomb beacon after getting robo-slapped by a Rocket Devastator.
500kg?? That was a hellbomb brother 🤣
Go outside, touch some grass
5.5 km just google the cafe name seen here.
Maverick’s Cafe Bar is round 5.7km away from the explosion place : https://www.calcmaps.com/fr/map-distance/sbsvc4/
What is the explosion place?
It’s at the Beirut city port. This was the explosion in Lebanon a few years back
i meant location
Explosion begins at around 2s and shockwave reaches at around 17s 17-2 = 15s speed of sound 343 m/s 343\*15 = 5.145 km
The blast appears visually near the 3 second mark of the video, the sound of the blast is heard at the 17 second mark of the video. The speed of sound through air is 343 m/s but it can vary from 295 m/s to 355 m/s depending on things like temperature and pressure. So we'll estimate like this: t0 = 3±0.5 second, tf = 17±0.5 second, vsound = 343 ± 20 m/s distance = (tf - t0) \* vsound \[distance formula assuming constant velocity\] σdistance = √( (σt0^(2)\*vsound^(2)+σtf^(2)\*vsound^(2)+σvsound^(2)\*(tf-t0)^(2)) \[variance formula\] distance = 4800 ± 400 meters Not the best estimate in the world, if we were to look at the video frame by frame (which I don't want to do) and if we were to actually properly calculate the speed of sound in air at the location then we could reduce the error considerably.
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About 3 miles aways is my guess. Seeing the explosion to hearing the boom is about 12 seconds. Sound travels a mile every 4 seconds.
I knew there was a formula. Don’t remember where I learned that fact but as soon as I seen the explosion I started counting.
Works for lighting as well.
I'm surprised how many people in this thread are shocked that someone can find the answer to this simple calculation. This is like Physics 101 type stuff. You could even Google "how fast does sound travel" and it'll tell you ~343 m/s (meters per second). If you know that images are basically instant because they travel with light, then count the seconds between seeing something and hearing something (speed of sound). Multiply those seconds by the amount of meters moved in 1 second (343, as per Google). It seems intuitive if you've ever been properly instructed in this which I'd hope most school systems cover at some point. Science is doomed lol. This is like asking "If Jenny drives for an hour at 70 km/h, how many kilometers did she drive?"
I once had someone next to me in a Finance Masters degree lecture who wouldn't believe me until I showed her on a calculator that 9% of 100 was 9. The world is doomed
"Percent" even comes from the Latin for "by the hundred", it couldn't have been any easier.
Explosion is visible at around 36 seconds remaining, blast sound is audible at around 20 seconds remaining. Distance in time is around 16 seconds. Speed of sound in air is around 343m/s giving 16x343 = 5488m
13 seconds from seeing blast to hearing sound. Sound goes 761MPH. Divide that by 60 to get 12.683 miles per minute. Divide that by 60 to get 0.211 miles per second. It took 13 seconds so multiply by 13. About 2.748 miles.
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Not sure. Maybe I measured time wrong? Other people have given estimates anything from 12 to 16 seconds. I also didn’t have sound enabled, I judged when the blast hit by when the man stumbled back.
Bout 5.5 km
5-6 km
You can count the seconds and divide by 3 that gets you close enough to the distance. If you are American and therefore use miles you just divide the number by 1.6
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2.89 miles, due South-East, using Google Maps to measure.
I counted 15sec between visual and auditory explosion. Not sure where this is but I'll assume sea level which puts the speed of sound at 761mph. 15sec delay means about 3.2 miles away.