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Bouncing UK Children Cause Earthquake
Xibalba writes: "This is kinda cool. One million children in the UK jumped up and down simultaneously in an attempt to see what would seismically happen." This cries out to become an annual (and international) all-ages event. Bounce! Bounce! Gain weight! Bounce! Repeat.
Just let Steve Ballmer jump around a little again.
See, the children were in elementary school, which is a higher education than the journalist had.
Early estimates suggested 75,000 tons of energy had been released during the minute of jumping.
But drop that in one spot and it would have caused quite a big hole in the ground
They aren't actually suggesting that all of Britain's children be dropped in one spot to see how big a hole they'll make, are they?
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
nope, you just don't understand the richter scale
2 &lastnode_id=141724
an earthquake of 10 is not just 1 notch above an earthquake of 9. It's 10 times more powerful.
From http://www.everything2.org/index.pl?node_id=51531
Listing is: Richter Scale # - Amount great than Richter Scale of 1 - info
1 1 no noticeable effects...detected only by seismographs
2 10 only slightly noticeable even if close to epicenter
3 100
4 1,000 slight damage near the epicenter
5 10,000
6 100,000 moderate destruction
7 1,000,000 severe destruction
8 10,000,000 one of the most powerful earthquakes ever recorded
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Whew, thank God. When I read "Bouncing UK children" I thought they had been thrown out of the window or something!
http://www.straightdope.com/classics/a1_155.html
Stupider like a fox! - H.S.
I'd like to think you're joking, but since I'm not sure I'm going to reply anyway.
They were expecting the jumping to be equivalent to about a magnitude 3 earthquake on the Richter scale which is a common seismic event that shows up on seismographs but which people can't even detect. A significant quake will be more like a 5 or higher on the Richter scale. This scale is logarithmic so a 4 is actually 10 times more powerful than a 3, and a 5 is 10 times a 4.
Thus the scientists would have to have been mistaken about the impact of all that jumping by a factor of 100 to actually rattle people. Any scientist worth his salt ought to be able to estimate the effect of what he's doing more precisely than 2 orders of magnitude, especially if it might be dangerous for him to be wrong.
Note: The 10 times factor applies to wave amplitude, energy content scales by about 10*Sqrt(10) or 31 times from one level to the next.
We're British scientists. We don't need reasons to do things, just cool things to do.
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The Lameness filter can filter this.
For those /.'ers who sneer at reading linked articles the kids just went out and jumped about for a minute. No attempt at synchronization beyond a wall clock and some teacher calling out "OK Luvvies - jump about now!" There wasn't even an attempt to get the kids on a beat (apparently BBC1 couldn't be persuaded to play Queen's "We Will Rock You" at the right time ;-)
However as directly useless as this may be to science it's doubtless opened the eye's of Britians youth to what promises to be only the first of the many pointless exercises they will be required to go through in their lives, always a lesson worth learning.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
Everyone now, ready, set, go!
But in the years since, the seismograph has fallen to the budget axe, and Tiger Stadium has been expanded to hold over 90,000. So if a "squeaker" of a game like that ever was to happen again, the resulting earthquake may topple the Louisiana state capitol building and ring bells in Alabama, but no one on campus will know how strong it was...
The kids didn't actually jump simultaneously.
It wasn't simultaneously, otherwise the effects WOULD have definately been much greater.
There is a military command (I can't remember the exact order) given in a march that instructs marching soldiers to lose cadance when crossing a bridge. Failure to do so has been known to collapse bridges as the combined force of dozens of troops marching in unison is capable of creating a powerful ressonance.
"Everything you know is wrong. (And stupid.)"
Moderation Totals: Wrong=2, Stupid=3, Total=5.
I was in a dorm a few years back and the occupants did almost the same thing. All of us flushed our toilets (approx 400 toilets) simultaniously (timed to when the local news started). Dunno what the hell happened, but we flooded the basement somehow. (5 floors, we had a math guru time the floors, sort of a time on target thing, and the first floor flushed 4 seconds after the music started, 2nd 3 sec, 3rd 2 sec, 4th 1 sec, 5th as they heard it)
It was a while back...
1q2w3e4r5t6y7u8i9o0pqawsedrftgthyjukilo;p'azsxdcf
For our next big event, on signal, lets all simultaneously:
1) flush toilets
2) pick up a telephone handset
3) switch on a large electrical appliance
4) call for Chinese take out delivery
5) withdraw funds from the bank
6) visit the same web site
try { do() || do_not(); } catch (JediException err) { yoda(err); }
Lord Richter: "Do not be so proud of these children you've instructed; the power of one million bouncing children is insignificant next to the power of the Force..."
Commander of Child-Powered Earthquake Machine: "You don't frighten us with your scientist's ways, Lord Richter. Your sad devotion to that ancient profession has not helped you conjure up new fault lines, or given you clairvoyance enough to--urk! Ack! Ick! Urg!"
Prime Minister Tarkin: "Enough of this! Richter, stop jumping up and down on him!"
Lord Richter: "As you wish..."
This story reminded me of Tesla's Earthquake machine which, if you believe the stories, demonstrates just how much damage you can inflict when you hit the resonant frequency with a modest amount of power.
I suspect the bit about sympathetic vibrations causing a bridge to collapse is mostly an urban legend, at least for modern bridges
l (in English)
It did happen on April the 16th 1850 in France, when a troop crossed a suspension bridge durong a storm near Angers (the Basse-Chaine bridge, over the river Maine) causing 220 soldiers to drown.
There's a good sum up of the event here (in English)
The cause is supposed to be the addition of gusts of wind causing the bridge to sway, and the troop marching steps, all giving a phenomenon of resonance.
and it even was reported in the New york Herald at the time :
http://www.goodbyemag.com/may00/herald-deaths.htm
however, the causes are very similar to what happened to the Tacoma Narrows bridge, on nov 07 th 1940, catastrophic wind swaying.
I'm happy to share this part of my history,
Baz.
While I've certainly heard of this before, its effectiveness may well be limited.
Has anyone heard of the Millennium bridge across the Thames in London? Pedestrian suspension bridge, kept in suspension sideways IIRC so no tall pillars or overhead cables. Problem was, it wobbled. It wasn't damped enough so could sway quite noticeably from side to side and was closed. There was then a controlled re-opening for people who knew full well it would wobble. They then realised they were going to have to have squads of staff to break up those maliciously walking in step and so amplifying any forces.
The problem, though, was that with the bridge wobbling sideways people were inevitably going to try and stabilise themselves so as not to collapse. So, as you feel a wobble sideways you brace yourself against it and so exert a sideways force on the bridge which makes it wobble in that direction... and you get the idea. Everyone quickly falls into step with each other, so amplifying the wobble...
Spot the problem.
Greg
(Inside a nuclear plant)
Aaaarrrggh! Run! The canary has mutated!
"Route step, march!"
Or for the pendantic...
What would that be? The people who dangle?
</pedantic>