Wednesday, May 30, 2012

And now for the Orkneys

My tour of northern European islands continues with my departure for Scotland and the Orkney Islands tomorrow. It's a wonderful 7am flight out of Keflavik, which means I should be sleeping - gotta catch the airport taxi at 5 Here's a view of our room in Reykjavik - make of it what you will... The ADD Bird room

Sunday, May 20, 2012

I didn't think I would get a chance to see the eclipse, but the clouds opened up and I dragged my wife up the hill to see the eclipse. I snagged a pair of binoculars and an empty pizza box to act as a screen. Untitled Untitled

Monday, May 14, 2012

Epic Eruption was, well... Epic.

It's the end of the semester. I'm in the process of grading the last final exams and wrapping up grades. As a way to finish off some of the extra liquid nitrogen and a little end-of-semester stress release. On friday, Todd Z - who blogs over at "Talking Physics" ran the high speed, while I basically goofed off in front of the camera. Here's a little mashup of the festivities:

This one made full use of the rubber ducks hinted at in the first version. Needless to say, we got some good hang time on those ducks. Todd wasn't around, but my pals Laura (best. department chair. ever.) and Kelly McCullough (Sci-Fi/Fantasy author and self-heating cat furniture) was able to trigger the camera. Well, really "clench with surprise" at the explosion - which had the added benefit of pushing the button at the same time.

The bit of "action hero" footage was suggested by Steve  Gough over at Little River Research & Design - I guess it's a "thing" that cool guys don't look at explosions. So this was me trying to be cool or something.

Don't forget the educational potential here - there's the geological, plinian eruption style and data from the "volcaniclastic" ejecta to be gained. There's a whole slew of mechanics questions you can ask/answer. Such as why does the trash can jump? And how much energy is released by the expanding nitrogen gas? (compare the measurements from the moving can/water to the ideal gas law, perhaps). Or, how high does the eruption column go? To help you out with that last bit, I strung together a couple of the slow-motion clips to help you figure that out:

My colleague teaches a "Physics for Video Game Design" course and they estimated about 1/1000th of a pound of TNT equivalent. That seems a little small to me, but then again TNT is pretty explosive stuff.

Tuesday, May 08, 2012

Saturday, May 05, 2012

Wise words, grasshopper.

So, is wisdom a product of hindsight or foresight?
Grading the last midterm I came across this astute observation.

Friday, May 04, 2012

Slomo Friday

Two slow-motion movies, provided without comment. But feel free to make comparisons:

Oh, it's Star Wars day?

I'd be more excited about it if George Lucas hadn't clearly demonstrated that he's not interested in catering to our childhood imagination about how it was for us. It's what he wants to do to it again. And again...

But Star Wars as an idea, as a cultural "thing" is cool. To acknowledge this, I point you to a re-creation of a whiteboard sketch I did for my soil science students. Where the tetrahedral lattice of the clay ended up looking like a Jawa sand crawler:

Thursday, May 03, 2012

Thurs-Demo: The One That's Reinforced

Another thing that you can do with the Emriver plastic sand - build reinforced sand castles using layers of window screening for the geotextiles.

Here you can see the individual compacted layers of sand in between the window screen material.  With about 80 pounds of weight on top of it.

Here I am pondering the strength of mechanically stabilized backfill.

And add a professor to bring everything up to over 220 lb (about 100 kg). All that supported by a humble little pile of reinforced sand.

To the Bridge of Khazad-dum, hurry!

You shall not pass!

Fly fools!

Fisheye Test

Here's a little test of the fisheye lens:

Wednesday, May 02, 2012

SuperWHAT now?

Again? Really? Sigh.

Bad Astronomer goes through the sequence - again. And here's the math I sketched out last year.

Really, though - this was just an excuse to post my moon-in-underpants picture again.


What's that? Oh, that's just a 4x4x4 inch sand castle I made out of geofabric and Emriver plastic sand.

With 56 pounds of iron sitting on top of it. That's a bit over 25 kilos for the rest of you.

Tomorrow, I make one that will support a person... maybe even a person carrying this 56 pounds of iron.

Is it summer yet?

The semester is drawing to a close: less than one week of lectures remain. That doesn't mean people around here aren't already a little punchy. One of my friends, Mike (an english professor), stopped by the Dirt Lab to see what was going on. He immediately saw the narrative potential of the Em2 stream table. So a few of us set about re-creating a dramatic scene from the Lord of the Rings:


Which got me thinking of another scene:
Give us the halfling, she-elf!

If you want him, come and claim him!

As the riders set foot in the Bruinen, the waters begin to rise...

...and churn about them...

...sweeping them away downstream...

...amidst a roiling cloud of water and foam that resembled horses.

With their enemies thwarted, our heroes can rest and recover in Rivendell.

This probably isn't the geekiest thing done with an Em2 stream table, but I think it comes close.

Air-Filled Ballloon

I've popped many a water balloon - they're so satisfying. But what about an air-filled balloon? They're cool too. But I had to add some talcum powder inside to make things interesting. Even at 5,000 frames per second, the whole thing is over too quickly (maybe I should duel him left-handed?).