Prince Rupert's Drop Glass

[fossilfly]

I found a short clip today about Prince Rupert's Drop Glass, in which a molten drop of glass is dropped into a bucket of water to solidify. After cooling the drop, with a gossamer tail of glass, is relatively strong and can withstand hammering. However, once the glass "tail" is broken, the drop of glass explodes. Check out the video to see what I mean. Very cool:cool:

http://www.boingboing.net/2008/03/11/curious-property-of.html

[jelicanefertiti]

FASCINATING , by the way why is called 'Prince Rupert'( just trying to learn )

[fossilfly]

FASCINATING , by the way why is called 'Prince Rupert'( just trying to learn )

Good question, I really don't know! LOL
I googled it and found this on wikipedia:

http://en.wikipedia.org/wiki/Prince_Rupert's_Drop

The crazy part is the cracks travel up to 4200 miles/hr! I guess thats why they explode so forcefully.

Heres the quote:

Recently an examination of the shattering of Prince Rupert's Drops by the use of extremely high speed video (or so called "stop motion" techniques) [1] (http://www.physics.purdue.edu/colloq/99-00/chandrasekar.html) done by Dr. Srinivasan Chandrasekar at Purdue University (http://en.wikipedia.org/wiki/Purdue_University) has revealed that the "crack front" which is initiated at the tail end, propagates in a disintegrating drop within the tensile zone towards the drop's head at a very high velocity (~ 1450-1900 m/s, or up to ~4,200 miles per hour).
Due to glass's inherent transparency, the internal stress within these objects can be demonstrated by viewing them through polarizing (http://en.wikipedia.org/wiki/Polarization) filters (http://en.wikipedia.org/wiki/Filter_%28optics%29).
The drops were supposedly discovered around the 1640s by Prince Rupert of the Rhine (http://en.wikipedia.org/wiki/Prince_Rupert_of_the_Rhine) (1619–1682), grandson of James I (http://en.wikipedia.org/wiki/James_I_of_England) and the nephew of Charles I of England (http://en.wikipedia.org/wiki/Charles_I_of_England). Legend has it that the king would often use the drops as a practical joke in his court (http://en.wikipedia.org/wiki/Court). He would give a drop to a courtier and then break the tail, causing a small explosion in the hand of the then surprised person.