Tuesday, September 25, 2012

Now this is how you teach physics

Liquid nitrogen in a sealed plastic bottle, a trash can full to warm water to speed the boiling, and 1,500 ping pong balls for "just because".



That's one Professor that knows the best demonstrations always include Earth Shattering Kabooms.

Hat tip: El Reg.

9 comments:

Anonymous said...

I am thinking that it won't be too long before some pasty faced bedwetter complains that the demonstration is too dangerous.

Ruth said...

Oh thats awesome....

WoFat said...

Yeah!

Anonymous said...

The professor stuck his head over the trash can. Not smart. I understand that a 2l bottle with a handful of crushed dry ice and a little warm water will explode less than 3 seconds after screwing the cap on. Not smart.

Ken O said...

Not exactly. It largely depends on other factors. For example, a one ounce chunk of dry ice in cold water took about fifteen minutes to explode a two liter at my home. The same sized chunk in hot water Detonated much sooner.

Bob said...

Can you imagine Mr. Moose on the old Captain Kangaroo TV show having access to liquid nitrogen?

David said...

Back in the 70s my college chemistry prof was talking about exothermic and endothermic reactions. Through his whole lecture he had a ring stand with a large porcelain crucible on it suspended over a pail of sand. Eventually he explained that he was going to start a thermite reaction in the crucible. He added the reagents he needed, then a catalyst (which he refused to identify for us) then grabbed his notes, his jacket and ran out of the room.

When the reaction started it gave off enough smoke to set off the smoke detectors, and threw sparks into the 5th row of the lecture hall. We watched the fireworks show as the bottom of the crucible glowed red hot and eventually melted and dropped the whole mess into the bucket of sand.

As the fireworks abated the professor peeked back around the doorframe and said "The University hates it when I do that. Read chapter 12 for Monday and have a nice weekend" then he pointed to a student sitting in the front row and asked him "Would you mind putting that newspaper that is burning near your seat out." then he left.

The student kicked the burning paper out into the front of the room then stomped the fire out as the rest of us left.

It too bad we didn't have video camera back then...

sconzey said...

I didn't take physics or chemistry beyond high school. I remember we had an NQT who chucked a chunk of potassium in a bucket of water. He mentioned that when he was at school you were able to use caesium too, which gives a bigger bang.

Unknown said...

video has been taken down. Bummer