Posted on 07/22/2013 7:01:13 AM PDT by Red Badger
The Pitch Drop experiment set up in 1944 at Trinity College Dublin's School of Physics is one of the world's oldest continuously running experiments.
The experiment was established to demonstrate that pitch is a material that flows, albeit with an incredibly high viscosity hence extremely slowly. Also known as asphalt or bitumen, pitch appears to be solid at room temperature.
Whilst pitch has been dropping from the funnel in Trinity since 1944, nobody had ever witnessed a drop fall. It happens roughly only once in a decade.
In May of this year, with the latest drop about to fall, Professor Shane Bergin broadcast the experiment via the web. On July 11th, the drop dripped. You can see a time lapse video of this here.
Tracking the evolution of the drop, Professor Denis Weaire and Professor Stefan Hutzler, and David Whyte calculated the viscosity of the pitch to be 2x107 Pa s, approximately 2 million times the viscosity of honey.
Commenting on the significance of the demonstration, Professor Shane Bergin stated: "People love this experiment because it gets to the heart of what good science is all about curiosity. Over these past few months, there has been constant chat about when the drip would drop. I watched the time lapse video of the pitch drop falling over and over again. I was amazed. This was the first time this phenomenon was ever witnessed!"
The School of Physics at Trinity College Dublin has many old demonstrations and ancient experimental kit. The Pitch Drop experiment was begun when Nobel Prize winner Earnest Walton was head of the department.
The University of Queensland have a similar experiment that was begun in 1927. The Guinness Book of World Records ranks this as the world's longest running experiment. Whilst 8 drops have fallen in this experiment, nobody has ever witnessed one fall.
Whilst it will be roughly another 10 years before the next drop falls, you can look at the live experiment here.
In 1927, a researcher at the University of Queensland in Australia began what’s widely recognized as the longest-running experiment ever, the so-called “pitch drop.” It’s a simple set up: fill a flask with tar pitch and let it ooze out the bottom to see how quickly it flows, and eventually it makes a proper drop that falls down about once every ten years or so. Tar pitch is a substance that appears to be solid, but in fact is actually a slowly flowing liquid. However, since the beginning of that experiment human eyes have never actually seen the pitch drop from the bottom of the flask the last time the Queensland experiment dropped, the webcam that was set up to see it failed at precisely the wrong moment.
Ah misprint. Very confusion.
They must mean 2x10^7 Pa s
More like 20,000,000 Pa S
its probably supposed to be 2 time 10 to the 7th power
2 x 10^7
This is yet another example of the phenomenon of media trust... If you KNOW the topic, you can see the media are clueless... which should make you suspect their level of understanding of anythign else they report
If you write software, and you read an article about it often it is is ridiculously lame. This is true if you are a roofer and you read an article about roofing, or a painter, or an engineer, etc. etc.
Thanks. I presume that’s Pascal-Seconds
So true.
I have no experience with Pa S so 1 Pa S or 2 billion Pa S means the same to me.
bowel movement
You’ve got that right! The incessant speculation about the speed of dropping of a royal spawn makes watching pitch drop all the more appealing. It only happens about every 10 years so I can ignore it for long periods.
What has the British royal spawn to do with the real world? Nothing, nothing and....NOTHING!
I have no doubt the author and his editor (if he has one) have no inkling how to use scientific notation.
I went to the site, it’s like that there too.
That’s correct.
I should have read all the comments first, as others had already posted what I did. Sorry for the redundancy.
Maybe if you eat a pound of cheese. :)
AGREE!!
What if someone walked by and accidently bumped the table?
LOL!!!
Like another language, it is indeed.
*One I cannot speak mind you ; } but our eldest does - fluently :)
Thank You Lord, for blessings without number.
Tatt
Anyone needing an experiment to know that pitch is not a solid and will flow is an idiot. Hence, a college did this.
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