Original URL: http://www.theregister.co.uk/2012/09/22/liquid_nitrogen_and_ping_pong_balls/

Made for each other: liquid nitrogen and 1,500 ping-pong balls

The latest bombastic demo by student-pleasing UK prof

By Rik Myslewski

Posted in Science, 22nd September 2012 00:06 GMT

Video It's the rare scientific mind that has the pure intellectual chutzpah to tackle a problem that has troubled boffinry since the discovery of cryogenics – namely, "What happens if you combine liquid nitrogen with 1,500 ping-pong balls?"

C'mon, don't tell The Reg that question hasn't crossed your mind. It hasn't? Well, then you don't share the experimental derring-do of Dr. Roy Lowry, an associate professor in the Faculty of Science and Technology at the UK's Plymouth University.

With the help of two stouthearted assistants, Lowry demonstrated the results of pouring one-third of a liter of liquid nitrogen – which boils at −196°C (−321°F) – into a one-liter plastic bottle, tightly capping it, placing it in a tub into which had been poured a bucket of warm water, and allowing the heat from the water to more-speedily gassify the LN2.

To better demonstrate the explosive power of that expanding gas, Lowry filled the remaining space in the tub with 1,500 ping-pong balls. Why add those bouncy li'l fellows to the mix? As Lowry explained in a video of the demonstration, "For no other reason other that we thought it would be quite nice."

And it was:

This lovely bit of "Ain't science fun?" classroom hijinx was not Lowry's first attempt to mix science with tomfoolery in the persuit of pedagogical payoff. He has also roasted jelly babies in the name of science, and set the world's record for near-simultaneous fireworks-rocket launches: 56,649.

Only a fortunate few science students have had the good fortune to be taught by a professor like Dr. Lowry, a man who understands the pure, visceral pleasure of 'splodin' stuff. ®