Saturday, October 31, 2009

Momentum treats with a few new tricks

The Book of Phyz section on momentum has been updated with new curriculum materials. And most of the old stuff has been refreshed.

Book of Phyz Momentum for High School Physics

I've been enjoying Keynote's animations and Findsound's sound effects. So don't miss the links to the zipped QuickTime presentations. I can't really post editable Keynote files or PowerPoint exports of the Keynote presos. The fonts never make it through, and animations and transitions are typically lost in translation. The interactive QuickTime presentations are the best I can do. But they don't seem to play well as web pages, so I zipped them. Download them, expand them, and play them. They're pretty engaging when used in conjunction with their corresponding paper documents in class.

Indeed, when I was out two days this week on jury duty, I left some interactive QuickTimes from this unit for the substitutes to advance through. It was the closest thing to a lesson presentation I could reasonably hope for.

Oh, and don't miss the link to the stream of Jearl Walker's Kinetic Karnival episode, "Forces and Collisions."


UPDATE: There were some typos on the PhyzJob: Conservation of Momentum Number Puzzles - Part 3: More Puzzles. They've been fixed!

Tuesday, October 20, 2009

Purity of Essence: The Rainbow Conspiracy

I fear this YouTuber is entirely sincere. The thought will haunt my dreams.

It's especially troubling that this woman claims to be a Northern Californian. And in fairness, she might have been heavily into drugs 20 years ago. Her recollection of sprinkler rainbows may have been clouded by hallucinogens. I speculate, grasping at straws in hopes of making sense of this science education epic fail.

So. Very. Troubling.

Hat tip to Skeptical Teacher, Matt Lowry.

Sunday, October 18, 2009

The World Spins Madly On

I was a fan of Mad Magazine in my youth. I'm a fan of the Weepies now. I'm a fan of the Exploratorium and their clever optical delusions. And Halloween is coming.

With all that in mind, click this link if you dare. (And be patient. It will need several seconds to load. Don't worry: your money back if you're not satisfied!)

Fall harvest of new & improved UCM & Gravity stuff

I was deep in the midst of lab manual authoring this time last year. So this year, I got the chance to write new material or update old material for the Uniform Circular Motion and Gravity unit in Physics 1.

The full page of curriculum materials is here. The new or improved items have asterisks bracketing their numbers.

I'm happy with the way the "Forced to Go in Circles" presentation came out. Sight, sound, and motion! Use it with the Springboard and I think you'll agree it's worth the time to download.

The two new "Will It Go 'Round In Circles" demos make use of a rotating platform (Arbor and Pasco have 'em) and Pasco's Visual Accelerometer. And, oh yes, the mechanics use for the Skinny Fish Tank (Arbor's Laser Viewing System) is exploited.

The TechLab uses PhET's excellent My Solar System orbital mechanics simulator.

Jearl Walker's Kinetic Karnival

All six 30-minute episodes of Jearl Walker's classic television series, the Emmy-winning Kinetic Karnival, are available online at Walker's MySpace page. I recommend watching them before showing them in class, although I'm sure you'd do that anyway. There are a few brief moments that sensitive educators might find objectionable. Most of us find ways to work around such trivialities, but it's always best to be aware.

I developed video question sets for episodes 1, 2, 3, and 5. Students answer them while the video is in progress. They're up as PDFs in The Book of Phyz.

Here's a one-stop collection of Kinetic Karnival links for your convenience.

1. Forces and Collisions [impact time and contact area]
In this episode, Jearl proves his virility and masculinity by chopping concrete bricks with his bare hands and volunteering as the meat for a “nail sandwich.”
Video Stream - Question Set - Key

2. Rotation [circular motion and conservation of angular momentum]
I show this one in two distinct segments (one in my Physics 1 course, the other in AP Physics 2). The first third is devoted to circular motion. The second two-thirds is devoted to angular momentum. Do I dislike the blending of these distinct topics? Yes. Do I have the talent and ability to produce my own series? Not so much. In any case, this episode features Jearl in a swim suit!
Video Stream
Video Question Set 1 (UCM) - Clothoid Loop (short preso) - Key
Video Question Set 2 (Angular Momentum) - Key

3. Fluid Flow and Friction
In this episode, Jearl debunks the drain swirl myth from the bathtub, describes an early dating disaster, explains the tablecloth trick, and hangs a spoon from his nose.
Video Stream - Question Set - Key

4. Viscosity [non-newtonian fluids, quicksand, and corn starch]
Jearl enjoys tinkering with viscous and non-newtonian fluids. He gets stuck in quicksand and jumps feet-first into a pot of unflavored gravy.
Video Stream

5. The Leidenfrost Effect [heat transfer and phase change]
Arguably the best program of the series, though it does contain a "politically-incorrect/racially insensitive" moment. When Jearl complains about "the problem" with iron-cooked crepes, you might find the mute button on the remote control of your playback system. A few moments of mute will spare you an apologetic discussion afterward. Features the hand into molten lead, liquid nitrogen in the mouth, and firewalking.
Video Stream - Question Set - Key

6. The Science of Cooking
Jearl prepares a meal for a dinner date with a young lady. Along the way, he describes the physics and chemistry of a variety of dishes. And the date turns out as you might expect.
Video Stream

Tuesday, October 13, 2009

Wasn't that a mighty storm?

There's a great sequence in the Reese Witherspoon/Matthew Broderick comedy Election, showing Broderick's teacher character teaching the same thing year after year. His chalkboard diagram is the same year after year. Only his clothes change.

You teach at a school for 24 years and you might think you've seen it all. But you haven't.

I've become somewhat accustomed to the delicate fragility of our school's electrical system. It takes very little in the way of wether to shut our electricity down.

And so it was with our first-of-the-season storm today. We weren't too deep into our first two-hour class when out went the lights. Nothing new? Oh, but this time there was a twist. All the neighboring classrooms had lights. Just not mine. My outlets seemed to work, but my projector would not light.

My mistake: to try to keep teaching. Can you blame me, though? I am a teacher. And the thing about two-hour classes? You better have some variety planned. Some of that variety might include presentations and video clips. No dice when the power is out.

After 20 minutes or so, an announcement came through the PA to the effect that, "The electricity is out. We're on it. Keep teaching. Send a student for a flashlight if your classroom doesn't have one. And don't forget to take roll. If you can't take roll via the online system, do so by hand."

After some failed wrangling, I had to abandon Plan A and go to Plan B. But time was wasted. And some of the lessons I planned for the two-hour period went untaught.

The power continued to come on and go out stochastically throughout the rest of the day. It's up. It's down. Up. Down. No, back up. No, back down. Light. Dark. Repeat. If there is a content-based lesson that engages student under such circumstances, I am unaware of it.

When the power came back one time, an announcement was made to the effect that, "Teachers, please take roll; the online system is up."

You would be forgiven if you came away from the day thinking that the most important thing that happens at school is The Taking Of The Roll. The harsh reality is that you are correct. Just as television programs serve as vehicles to deliver commercials, instruction serves as a backdrop to space the intervals at which attendance is taken.

One thing I can always count on during power outages is our classroom set of laptop computers. They work like a charm. In my second two-hour class, we used them for a while. We could have done a full sensor-based computer lab if we needed to (the sensors draw power from the computers).

I remember much worse weather, but no power failures during my schooldays in Michigan. Sacramento in general and Rio in particular are simply very delicate flowers when rain falls and wind blows.

Oh well, tomorrow's another day. Maybe I'll be able to teach.

Going ballistic at one million frames per second

Megahigh-speed video.

You might want to turn the sound off for this one. Sound is not captured in high-speed video, so the videographers add something from their own library, which is certainly superfluous and might be annoying.

According to the commentary, there are 1,000,000 35-kilobyte jpgs per second, or 35 GB of information stored for each second. And if you ever had difficulty intuiting that bullets are bits of solid lead that melt upon impact, watch closely!

Hat tip: Huffington Post (includes links to more high-speed stuff).

Sunday, October 04, 2009

Post-PTSOS1 spotlight: Secrets of the Psychics

The episode of NOVA devoted to the work of James Randi, "Secrets of the Psychics," appears to have gone out of print. Resellers at with VHS tapes to sell are offering it for $999.99.

Thankfully, the episode has been posted to YouTube.

I wrote a question set to accompany presentation of the program.
NOVA: James Randi's Secrets of the Psychics

For the answer key, scroll to the bottom of Skepticism in the Classroom and download the Teacher PDF file.

Friday, October 02, 2009

What to do with this?

There is a lesson in there. And the physics would make Hewitt kiss the tips of his fingers. But... go ahead; watch for yourself.
Car bowling?