Wednesday, May 17, 2017

Science Wednesday Prince Rupert’s Drops

I found the "mystery" of Prince Rupert’s drops fascinating for several reasons.  First the story:
Since the 17th century, Prince Rupert’s drops have puzzled scientists. The drops are made by dipping a bead of molten soda-lime or flint glass in cold water, which forms a tadpole-shaped piece of glass. While the head of the drop is incredibly strong and resist everything from a hammer blow to speeding bullets, just flicking the tail of the crystal can cause the whole thing to burst into powder. Now, as David Szondy at New Atlas reports, researchers have finally figured out the secrets behind these drops.
In 1994, researchers used high-speed photography to record and analyze the way the drops shatter, Lisa Zyga reports for Phys.org. They concluded that the surface of the drop has high compressive stress while the interior of the drops is under high tension. While that combo makes the head very strong, it’s not in equilibrium, which means even a slight disruption at the tail causes the whole thing to destabilizing and fall apart. In fact, the cracks move at 4,000 miles per hour, which pulverizes the glass.
But it wasn’t until recent technological advances, however, that could researchers examine the stress distribution in detail. They used a transmission polariscope, a type of microscope to study the tensions within the glass. By sending red LED light through the drop while it was submerged in a clear liquid, they could measure how stresses in the drop slowed down the light, giving them a rainbow-colored optical map of the forces within the drop. Using mathematical models they then calculated the various interior and exterior forces. The researchers published their results last year in the journal Applied Physics Letters.

Check out the video at Smithsonian.

Now as to why this caught my eye.  If you had asked me in my fifth or sixth year of college about this I could have rattled off the answer and it would have taken a few hours to work up the rough math to support my answer.  It never occurred to me that such a phenomena would be considered a mystery.

Second is the use of polarized light to reveal stress.  I did this in my first real job designing aerospace fasteners.  We even made up hundreds of samples to prove the design was not stress inducing and handed them out to disbelieving colleagues.

Regardless, really cool stuff. 

Why mention this today?   Google is celebrating the 115th anniversary of the Antikythera Mechanism's discovery with a new Doodle.

39 comments:

Rob Dawg said...

House +$950
Ford -$100

Strange times.

LBD said...

Nice to see the scientist relate the value of the properties in this glass to common use in cell phone screens. Most of the time they leave many of us with you get paid for this?

Rob Dawg said...

BofA off 5% at the moment. Liz cheers.

Rob Dawg said...

> ...you get paid for this?

All my best jobs involved breaking things. Sometimes really big things. My biggest fear was that they'd catch on and start charging me instead of paying me for it.

LBD said...

Sounds like racing. We paid for parts to stress test and break them. LOL! what fun we had. :)

Rob Dawg said...

You pulled over to the side. We fell out of the sky. We broke our stuff on the ground so we wouldn't have to break them in practice.

As an aside. You can buy for $2400 a "model" airplane engine weighing 4kg all in that produces more power than the original Wright Flyers. Gives me bad ideas.

Lawyerliz said...

Yaayyyyy!!!

LBD said...

I have bad ideas everyday. Expensive ones, luckily I like having my wife around as she says your next wife can pay for it.

Rob Dawg said...

BofA down 5.5% now. Only 94.5% to go. ;)

Financials getting hit. Strangely the Utilities are up. Unusual disconnect. More usual are the gold and silver stocks that are doing what they are supposed to do and going in the other direction. Finally.

Is this the start of return to normal after the lost decade?

Lawyerliz said...

Why is B of A (may it be destroyed) down??

Lawyerliz said...

Over 6% now!!!

Rob Dawg said...

> I have bad ideas everyday. Expensive ones, luckily I like having my wife around as she says your next wife can pay for it.

That's my wife too! Can we charge her with bigamy?

Still, we live in a world where two weed whackers, a hundred pounds of aluminum/carbon/cloth and a little engineering can make an airplane there might come a time when we don't have to ask our better half.

Rob Dawg said...

> ... why...down?

A case of returning fundamentals. Before; the stock price is going up so buy. Now; why own a stock that has gone way up and doesn't do anything special in any special way?

Rob Dawg said...

Morgan Stanley -6%
Giant Squid -5%

Overdue.

Cinco-X said...




https://www.sciencenews.org/article/chaco-canyons-ancient-civilization-continues-puzzle?tgt=nr


\Pueblo Bonito, the oldest and largest of a dozen huge stone great houses in Chaco Canyon. The structure was built, along with a range of smaller structures, between about 800 and 1130.

Notice that this locations was basically only habitable basically during the Medieval Warming Period, which mainstream climate scientists say never happened...

Rob Dawg said...

> Chaco Canyon

I've been there.

How to say this?

Okay. There's no way anyone would call this a "bucket list" destination. Once you go there and really investigate the site I challenge you to claim it shouldn't be on everyone's bucket list. The only reason to not to sing praises is because the site cannot handle the traffic it deserves.

Rob Dawg said...

> ... between about 800 and 1130.

Notice that this locations was basically only habitable basically during the Medieval Warming Period, which mainstream climate scientists say never happened...


More a case that should be made for a "Southwestern NA" wet pattern. Is the dry now or the wet then normal? Above my pay scale.

Lawyerliz said...

Up almost 200$

LBD said...

Used Dewalt rip saw motor, Weed wacker lower shaft and a trolling motor prop. Soon to be a functional trolling motor from scrap. Fun. :)

Cinco-X said...

I'm sure they need one of those in Mudville...

Lawyerliz said...

Planted yet more marigolds and clipped regular grass. O

Lawyerliz said...

Maybe 120 more marigold plants would finish the marigold part.

Lawyerliz said...

Dow down 378. Wow.

Rob Dawg said...

Less than 2%. We forget that 2% is little more than random walk.

Lawyerliz said...

MY pink rose has a couple of branches with a dozen or more byds. Take that, entropy!

Lawyerliz said...

A nice 10% correction would be appropriate.

Lawyerliz said...

The stock market never goes down! Hahahahaha hahaha.

Rob Dawg said...

I can see 5-6% but 10% would break too many structural foundations. The recovery from the Great Recession is not strong enough to withstand even that much. Besides there isn't any other place to go.

Lawyerliz said...

Special counsel appointed!

sm_landlord said...

> Special counsel appointed!

In related news, Franco is still dead.

Lawyerliz said...

And the Pope is still catholic

Lawyerliz said...

What if he fires the special presecutor?

Lawyerliz said...

What will the stock mkt do tomorrow?

Lawyerliz said...

Less than 4 months. Shakes head. Where is everybody?

Rob Dawg said...

If I knew what the market will do tomorrow I would not share. Not sorry. If I knew then sharing would change that.

sm_landlord said...

> What will the stock mkt do tomorrow?

"It will fluctuate".
--J.P.Morgan

Lawyerliz said...

Fluctuate wildly?

Lawyerliz said...

It was a rhetorical question. Now there is somethING about Paul Ryan and Russians paying and a tape??

LBD said...

To bad no one gave a s--t about Clinton's and Obama actions. This all the MSN and Dims can do. Sad.