Tuesday, December 21, 2010

The Moon when lit by all the sunsets in the world


I shot this at about midnight 12/20/10. We lucked out in Sacramento with a break in the overcast/rain. There was still some fast-moving, low, cloud activity. But the openings were sufficient to get some snaps.

Saturday, December 18, 2010

Bad Physics: Errant dispersion images are normal

I mean "normal" in both the common, regular sense and in the perpendicular, physics sense.

Attempts to replicate the classic prism image from Pink Floyd's Dark Side of the Moon typically fall victim to the error illustrated by the image above. The primary error is to show the incident ray and the refracted ray as normal (at right angles) to the air-glass boundary. It just seems like the rays should do that.

Add to that the fact that the prism has been replaced by a tetrahedron. And why are there divisions in the dispersed color bands? Absorption spectra? What's that glass tetrahedron made of?

Here's the Storm Thorgerson original:

Sunday, December 12, 2010

Ten new Wiseman tricks for Christmas

"New" for the 2010 holiday party season.



And don't forget these classics from 2009.



Get puzzled early and often at Richard Wiseman's Blog.

Sunday, December 05, 2010

Man Conquers Space (Teaser IV)

The original teaser for this film debuted in 2001. Here it is 2010, and the project continues to move forward.

Teaser III (2007) probably sums up the film's concept best. It's the story of what the space program might have been. The teasers have a documentary vibe to them. The MCS site states a hope that they'll have a release date in 2011 or 2012.

Friday, December 03, 2010

Small water beats big bacony beans!

Here's a fun pic from AP Physics today. We raced a solid can of baked beans (with bacon), c.1990 against a cylindrical bottle of water. A student suggested we try catching the result using the Casio EX-FH100's multiple exposure mode. We caught this at the very end of class. The water beats the beans. But why did it win? Sloshy liquid? Smaller radius? Hmmm...


The small water was placed in front of the big beans before they were released to roll down the hill. The farther they rolled, the greater the water's lead became.

Thursday, December 02, 2010

College Board makes their punt more permanent

A change is gonna come. Advanced Placement Physics B is to be split into a two year sequence. This much has been known since 2007. (Maybe even earlier than that.)

When is the change gonna happen, and what—exactly—is it gonna look like?

Details and a timetable have been promised time and time again. But there have been no deliveries just yet.

I last checked in June, since there had been a promise that details would be published in early 2010. The College Board's info page had been updated to reflect that the details would now be published in Fall 2010.

With Fall 2010 coming to a close soon, I thought it would be amusing to check in again. The page has again been updated, and the promise of details has been unhinged from the calendar.

"Reviews of AP Chemistry and AP Physics B courses and exams are complete and pending validation by colleges and universities. To allow educators sufficient time to incorporate course revisions into their teaching practice, the College Board will announce revisions two years in advance of implementation."

If the plan comes together for 2020, we'll be notified by 2018.

If nothing else, the latest revision does away with any need to update the web page. Gone is specificity. Intentional ambiguity rules!

[/rant]

Sunday, November 28, 2010

Multiple exposure photography

I'm dipping a toe into multiple exposure photography.

As is so often the case in such undertakings, I have no idea what I'm doing, but cannot resist the potential for grooviness.

I just started tinkering with this nonsense the day before Turkey Break. The image-compression trickery is built into my pocketable digicam, the Casio EX-FH100. My Fujifilm HS10 can do it, too. But the FH100 is much handier.

Click the image to see more of what I've been able to get so far.

Sunday, November 07, 2010

BMW ad: MythBusted!

Original post here. A BMW motorcycle is used to pull the tablecloth from under a banquet table with full formal setting. Go back and watch the videoclip.

Mythbusters story web clips: Tablecloth Chaos.

Executive Summary: Jamie was able to clear the tablecloth from under the banquet table setting. But only when he was able to get his custom bike to high speed before pulling the tablecloth. This required that the bike accelerate a distance with considerable slack in the rope.

The trick, as performed in the BMW ad, is not physics-ly possible. You simply cannot start from rest and jump to cloth-pulling speed on a motorcycle.

Shame on you, BMW.

Hat tip to Dan Burns via the AP Physics EDG.

Newton's Cradle telekinesis

My telekinesis training is moving apace quite nicely. I recently shared this result with my colleagues in the NCNAAPT.



The initial shock of the demonstration was somewhat subdued when I showed them an overhead view.



When I showed them the view from the static-cam, they no longer believed my claim of telekinesis.



O science! Must you take all the fun out of bogus claims?

I've developed a series of demonstrations involving the use of a rotational platform. The first two involve the use of Pasco's Visual Accelerometer. We do these demos in Physics 1. The third involves the Newton's Cradle. We save this one for AP Physics 2.

Demo 1: Will It Go 'Round in Circles?
What is the direction of acceleration for an object in circular motion? Tangential? Radial? Inward? Outward? Note: our students have completed the "PhyzLab: Going Through the Motions" prior to this demonstration, so they know the function of the Visual Accelerometer.

Demo 2: Will It Go 'Round in Even More Circles?
What happens to the magnitude of acceleration as the object is set farther and farther from the axis of rotation? The increase in radius suggests decreased acceleration. The increase in speed suggests increased acceleration. The Visual Accelerometer settles the matter.

Demo 3: Will It Go 'Round in Advanced Circles?
What happens when a Newton's Cradle is taken for a spin on a rotational platform? You already know the answer. In AP Physics 2, we develop an equation for the angle of the cord and interpret the equation.

And of course, a shout out to the legendary Billy Preston for the title.

Dark Side of the Laptop

If you're keen to show some attitude on your laptop (or iPad, or cell phone), you might consider MusicSkins.

I installed a Dark Side of the Moon decal on my MacBook Pro 15" and I gotta say, it rocks! It matches the wall outside my classroom.

And you know you're on to something when someone in the 2AM crowd at Denny's shouts out a compliment for your laptop. Oh, the decal is quite opaque: it blocks the light of the Apple logo. The #1 tech company in the known universe will have to muddle through without mobile advertising from me.

Saturday, October 30, 2010

The PhyzMasters of Junipero Serra High

My physics-teaching friend, Eric Plett, is a veteran of our PTSOS program. He's even been able to utilize some of The Book of Phyz curriculum materials in his physics classes.

One of the tangential jokes I sometimes sneak into my PTSOS shtick is that some years ago, some of my students developed a "call sign" ("gang sign") evocative of the "db" symbol placed on a bottom corner of my handouts. Over the years, the "db" hand flash has evolved into a few varieties. The point is to mimic the letters with one's fingers.

Anyway, Mr. Plett recently sent me this photo of his second period class.


















Here's what he told me about the photo:

"At the beginning of the year I explain that we will be using materials from a teacher friend of mine....

They enjoy the humor in your materials.

One of my students said, "There should be a call sign for Dean Baird." I told him that there is and showed him. Since then, the second period class loves to flash the sign. A few of them said they even wanted to do it in their senior photo but the dean wouldn't let  them because he didn't know what it meant.

Here is my second period class. The most enthusiastic of the bunch  (who originally asked about the call sign) is the one lying on the  floor."

It's assuring to know that Serra's dean has good sense. And my ginormous ego will be able eat for a month with a groovy photo like that!

Thanks for the tribute, Padres. Phyz on with your bad selves, and enjoy all of Mr. Plett's crazy demos this year!

Baseball noose? Idiot rope?

It's a testament to my lack of interest in major league baseball that the latest in big league woo escaped my notice. But when the playoffs started, I foresaw a series I might take an interest in. Texas vs. California (San Francisco).

As I began to watch televised baseball, I was troubled by the thick, ropey nooses that players seemed to be wearing by choice. These baseball necklaces looked bulky and awkward.

Having recently developed a lesson on the fraudulent nature of the Power/Balance bracelet, I knew how this necklace business was going to go if I looked into it.

So I looked into it, and it was everything I expected. The rope necklaces infused with aqua titanium. Wow: aqua titanium. The manufacturer/seller of this snake oil assures us that the titanium solute woven into the rope is a fountain of bio-energetic miracles. It increases circulation, reduces stress, balances bio-energy fields, blah, blah, blah.

There is, of course, no scientific evidence to support any of the claims. I'm pretty sure we were supposed to be so impressed with "aqua titanium" that we wouldn't think to wonder: What's titanium got to do with athletic performance? If titanium is a performance enhancer, should athletes pop titanium pills? Of course not.

Sports writers generally agree that baseball players are among the most superstitious athletes of all. I don't want to say there's an inverse proportionality between intelligence and belief in superstition. Actually, yes I do.

To me, those baseball nooses are idiot ropes. They're a billboard that identifies the wearer as a credulous consumer of worthless woo.

Don't get me wrong. I'm all for California's San Francisco Giants beating the snot out of the Texas Rangers. I love California, and I do not much care for Texas in general (though I do have friends in The Lone Star state).

But I don't mind seeing the rope-wearers on either team to get spanked by non-rope-wearers on a play-by-play basis.

For anyone to think that an unscrupulously-marketed rope necklace can boost their performance reveals a gullibility I simply can't respect. I know aging athletes are vulnerable to snake oil, and the stakes for MLB players are large. But we've been to the moon. It's time to turn away from superstition and move on to critical thinking and reason.

If you want better performance, train hard and take care of your body. Lose the neck rope and grab a jump rope.

Monday, October 25, 2010

O Jennifer and Michael, where art thou?

A few months ago, I did something simple yet strange. I compiled a list of the names of all the students I ever taught. Twenty-four years worth of names. Over 3000 in all.

Analysis of the list revealed that the most frequent male and female first names to pass through my classroom were Michael and Jennifer. I don't recall the exact number of Michaels, but I do recall there had been more than 70 Jennifers. Over three Jennifers per year, on average.

I recall once having four Jennifers in a single class. One went by Jennifer, another by Jen; one preferred Jenny and the other was Nif. (And yes, Nif was as charmingly quirky as her chosen moniker would suggest.)

Anyway, this year I am teaching neither a Jennifer nor a Michael. A blip in the continuum, I presume. But I could be wrong. Only time will tell.

Sunday, October 24, 2010

Web Video and Skepticism pages updated

The Web Video for the Classroom and the Skepticism for the Classroom web pages have been updated.

Some new links have been posted. Some new curriculum materials have been posted.

I'm not sure when you visited last time, so I don't know how much of it is new to you. Best to check them out for yourself.

But I'm pretty sure the lesson on Power/Balance hologram bracelets is new to everyone.

Time to flex your poker skills, physicists!

Your physics training was difficult and brain-bending at times. But the payoff extends beyond understanding the universe. Gather some friends and play some poker! For money! You're sure to win!!!

Or so they say in this recent piece from NPR. I, for one, am prepared to believe nearly anything Jennifer Ouellette tells me. (And I even knew how to spell her name without checking.)

So get out there and collect some cash. Daddy needs a new cyclotron!

Skeptical brilliance from xkcd

Sunday, October 17, 2010

My funny AP students

I'm really not that teacher. The favorite teacher that all the kids love. The one who knows all the students' names on the first day of school. Who's considered "cool" for being relaxed and understanding about homework, tests, labs, and exams.

I'm not an inflexible British schoolmaster from the 1950s, either. Or a high priest who accepts only the schools top 10% into his demanding, rigorous physics course.

I try to make my physics course the most challenging class students want to come to. Not easy to balance the "challenging" with "want to come to." And I don't presume to get it right.

But there are many teachers at my own school who do a better job of connecting with students on an interpersonal level. So I don't usually get anything like a student-delivered cake on my birthday.

But there was apparently some instigation for such a thing this year. And the work looks to have been inspired by the difficult FBD test they took on my birthday. I was out that day. The cake was brought in the following day.


A wonderful treat, and highly unexpected! ("Old Man Baird" is what my buddy, Rick, imagined my students called me about 15 years ago. I've incorporated it into my own classroom schtick. So now my students may well call me that. D-oh!)

Tuesday, October 12, 2010

Squirrel vs. Slinky

The squirrel is a simple creature motivated by two all-consuming drives. One of those drives is to eat. So if there's tasty bird food accessible from atop a pole, you climb the pole and get the tasty bird food.


The human male is a slightly more complex creature. His brain has lobes, and his hands have opposable thumbs. His drives include those of the squirrel, but he also hopes to demonstrate mastery over his domain. If the bird feeder he put in his yard is being attacked by a squirrel, he aims to thwart the squirrel to better serve the birds.


So the man engineers an elegant means to "squirrel-proof" his bird feeder using a simple Slinky. Higher thinking skills vs. basic instinct. Who will win? Watch to find out.


Tuesday, September 28, 2010

High school physics teacher: Genius!

How cool is this? California high school physics teacher, Amir Abo-Shaeer, has been named a 2010 MacArthur Fellow. Oh sure, David Simon (creator/writer for Homicide: Life on the Street and The Wire) was named. As was the designer of Verdana and Galliard fonts. Other geniuses were honored as well.

But Abo-Shaeer is the rockstar of the day, as far as I'm concerned. He teaches at Dos Pueblos High School in Santa Barbara. And he has been setting the river on fire.

MacArther Fellows receive $500,000, no strings attached.

Full Abo-Shaeer here.

Monday, September 20, 2010

Neverending updates and upgrades at phyz.org

I am back to being the sole proprietor of physics at Rio Americano. That hasn't been the case since 1995. But biology was up--way up--and physics was down.

The division of labor involved in producing Book of Phyz handouts for students is now undivided and reunited, all on my plate. I can get the district to do most of the printing by sending them PDF-based print orders. (That time spent learning PDFs in 1999-2000 is paying off.)

I always want to print the latest versions of all my curriculum materials. So I need to create PDFs of all my updated documents. The upside is that I can then post them to The Book of Phyz resource at phyz.org. As of this weekend, the whole of the Physics 1 first semester is online.

I'm also upgrading the PowerPoints. Of course, I don't use PowerPoint. My posted presentations are actually interactive QuickTime movies rendered by Apple's Keynote. When I started using Keynote, I went with a resolution of 800x600. Seemed hi-res at the time. Keynote scales when sending presos to the projector. So there was never a problem for me showing my presos in class.

But the rendered QTs did not fare so well. The looked jaggy. So when I can, I'm changing the resolution of the presos to 1650x1050 and re-rendering the QTs. They weigh in with many more megabytes, but they look much, much better. I'm trying to tag the upgraded presos as "HD."

And I just posted a new, Zen-like preso to accompany the Clever Dumbbell demonstration. No words past the title page! If you do the demo on a regular basis, you'll figure out how to leverage the preso. I also posted a simple preso to accompany the Cannonball demo.

Sunday, September 19, 2010

Significant figures, error, and "proofiness"

Professional scientists and engineers have to be skilled in the handling of error and the tracking of significant figures. High school students are not professional scientists or engineers. While I don't exclude any discussion of these issues in my course, neither do I dwell on them. We spend a day on them, and revisit them as needed.


I heard an interesting story on NPR's Weekend All Things Considered that made me think of how significant figures and error work their way into "everyday life." The piece is an interview with Charles Seife, whose latest book, Proofiness: The Dark Arts of Mathematical Deception will arrive on bookshelves this week.

Amazon's description of the book:

"Proofiness," as Charles Seife explains in this eye-opening book, is the art of using pure mathematics for impure ends, and he reminds readers that bad mathematics has a dark side. It is used to bring down beloved government officials and to appoint undeserving ones (both Democratic and Republican), to convict the innocent and acquit the guilty, to ruin our economy, and to fix the outcomes of future elections. This penetrating look at the intersection of math and society will appeal to readers of Freakonomics and the books of Malcolm Gladwell."

Listen to the NPR piece here. If you're not familiar with the story of the 65,000,038 year-old dinosaur, you shouldn't miss it.

The brief time spent on these matters in not for naught. Too much time on them pushes out actual physics out of the school year.

Saturday, September 18, 2010

Galileo was wrong? Oh I don't think so...

We've been exploring inertia in the physics class lately. We've been through some of my favorite demonstrations and will do a lab on Monday. We also watched the Mechanical Universe episode on Inertia, which includes the story of how Galileo used the concept of inertia to "set the world spinning." Spinning away from geocentrism and toward heliocentrism.

Recall that in the early 1600s, the rest of the Enlightened world was growing to accept the idea that Earth was but a planet circling the larger, grander Sun. Galileo was hoping to move Italy in that direction, despite its Church-enforced geocentric predilections. He imagined that his personal connection to the Pope might help him get away with it. And he was wrong.

But according to one Dr. Robert Sungenis, Galileo was wrong about heliocentrism, too.

Sungenis and his followers are modern-day geocentrists! Oxymorons? Perhaps. But they are scheduling a conference to share their beliefs. It's November 6 in South Bend, Indiana (near Notre Dame, they hasten to add).

Galileo was wrong and The Church was right, they claim. Science teachers, our work is never done.

The "Teach the Controversy" spoof T-shirts might sell well there. I hope actual scientists (especially well-spoken astronomers) attend. I'd pay for Phil Plait's registration out of my own pocket to get him there.

Thanks to Michael Shermer for spotting the conference.

Wednesday, September 08, 2010

Who knew lightning could be so annoying?

I'm somewhat torn here.

On one hand, it's a very kinetic presentation. Sight, sound, and motion. Nearly all of it could have been done in Keynote. (Do I need to add that nearly all of it couldn't be done in PowerPoint?) So yes, it's very flashy. And it beats traditional content-delivery presentations by a mile.

But for my tastes, it's too much. Too much information (mostly trivial), too fast. Too many wind-whoosh sounds to emphasize how quickly the information is whipping by.

Maybe I'm missing the point. Maybe this series is all about a big clusterdump of trivia presented as infotainment. If that's what it's trying to do, it does it well.

See for yourself.



OK, now let's get at the errors.
1. The "90% of people who are struck survive" line is terrible. The stat may be true, but the vast majority of those survivors suffer permanent, debilitating injuries.
2. With so many stock photos of cars, why did they have to choose a ragtop Cadillac? A convertible may not be so safe if struck by lightning. Better to have metal over your head. Canvas makes a lousy Faraday cage.

Tuesday, September 07, 2010

You CAN take the sky from me

A few years ago, I took a stubborn (er, "principled") stand against CompUSA. I wanted to buy a simple item from them, but the clerk would not complete the transaction unless I supplied personal information. Legal tender was insufficient. I bid her "good day" and walked out of CompUSA for my very last time. I purchased the same item across the street at Best Buy. I gave them money; they gave me the item. So old-fashioned.

Months later, CompUSA declared bankruptcy.

Tonight I tried to buy air at Target. A simple can of compressed air to clean the filter in the LCD projector I use at school. "I need to swipe your ID," the clerk demanded. "Why?" I asked. "Kids get high on the compressed air." "And you can see I'm not a kid; but here, here's my driver's license." I flashed her the ID. "No, I need to swipe it." "If you can't see than I'm not a kid looking to get high, I'm afraid I won't be able to do business with you. So why don't you go ahead and keep all these items?" I had some other stuff to buy, but nothing was such a crisis that I needed it at that moment.

I'm not a fan of surrendering more than money in exchange for goods at stores. I have no idea what they do or don't do with swiped driver's license data. But I do hear about identity thefts involving crooks who abscond with hard drives/data collected by merchants.

The merchants always apologize profusely for letting someone steal your personal information. But there are never legal/monetary consequences for them. So they don't feel compelled to protect the data as best they could.

If I decide to stay away from Target, I'm pretty sure they'll be OK without me. And if I can't buy air anywhere else without an ident card swipe, I'll be back to Target in no time. Otherwise, I simply can't do business with a merchant as paranoid as they are are stupid: a dumb nannystore.

A quick local news story on the swipe. Warning: it's a local news story...

But my immediate concern? How am I gonna get my buzz on without a can of air?

Sunday, August 29, 2010

Volgograd: the new Tacoma Narrows

If you're not signed up for Arbor Scientific's CoolStuff newsletter, you might have missed this.

The newly-opened Volgograd Bridge in southern Russia is experiencing a "resonance malfunction."



This is 70 years after the original Tacoma Narrows Bridge fell. Like Obi-Wan Kenobi, though, the demise of the Tacoma Narrows Bridge made it more powerful than anyone could have possibly imagined. Its oscillations of doom revolutionized bridge design and made it the most famous bridge in physics lore.



Russian authorities closed the bridge amid the resonant rippling, but reopened it days later following a safety inspection.

Still though, if you feel you were cheated by time out of a thrill ride on "Galloping Gertie," you might want to book travel to Russia. And you might want to do it soon. The original Tacoma Narrows Bridge carried traffic for four months.

Monday, August 16, 2010

STAR 2010 scores are up!

The 2010 STAR scores are now live. The high-flying Physics CST scores continue to climb.

Here's the statewide skinny:
72,766 students took the 2010 Physics CST
21% performed at the Advanced level
28% were Proficient
33% were Basic
11% were Below Basic
8% were Far Below Basic

The percent of Advanced and Proficient scores stands at 49%, up from last year's pack-leading 46%. The number of physics students earning Advanced or Proficient status has increased by 20% since 2003. No other subject-area test has seen anything close that kind of performance gain. Here's an obligatory Excel graph to show the story of the stats.

(click image to embiggen)

Congratulations, California physics teachers!

STAR 2010 results should be up soon

Keep a browser tab refreshed at the Standardized Testing and Reporting (STAR) website. I'll post an update when the 2010 results are up.

Monday, August 09, 2010

Time to ditch those "Scientific Method" posters

I never liked those Scientific Method posters. Or the equivalent lists that occupied Chapter One of so many science textbooks. They seemed too sterile and prescribed, and made science seem like a very clean business carried out by automatons.

So my pulse raced on my first viewing of The Mechanical Universe episode devoted to The Millikan Experiment. The narrative trashes the so-called scientific method. I thought that was fairly bold for a program devoted to science. The Mechanical Universe story laid out the fact that scientists are biased when they enter the lab. They usually know what they're looking for. And so on. It went on to describe how science succeeds despite scientists.

While working on my Master's degree, I found out that the "scientific method" as outlined in posters and schoolbooks was the creation of an education academician. No wonder I didn't care for it!

Carl Sagan suggested we need a Baloney Detection Kit when evaluating scientific claims. Michael Shermer describes, in detail, what such a kit might include. Here it is in video form.



I think a poster form of this Baloney Detection Kit would be a better use of precious science classroom real estate than those tired Scientific Method posters. Even better: a bulletin board where examples of pseudoscience can be added, organized by their most obvious baloney flags. Just a thought.

Saturday, August 07, 2010

Circumhorizontal arc at Angel's Landing

My brother, his wife, and I were hiking the strenuous and perilous Angel's Landing trail in Zion National Park earlier this week.

Physics lessons abound in work (elevation gain is 1500 ft), friction (footing), tension (chains), equilibrium (precarious balance), etc. But after returning from Angel's Landing to Scout Lookout, my brother directed my attention to a spectrum in the cirrus clouds above.


I had never seen such a color band in the sky. It was clearly the interaction of sunlight and cirrus cloud ice crystals. But it was at a much greater angle from the sun than the oft-seen 22° halo. The colors were spread wider and were more deeply saturated.

Upon returning to the connected world (which is a small world, indeed, when you're at the mercy of AT&T), I googled "cirrus cloud rainbow" and discovered that what we were seeing was a circumhorizontal arc (CHA).

A circumhorizontal arc lies 46° from the sun and is observed only when and where the sun is more than 58° above the horizon. We get more of them in the States than they do in Europe.

The heart of CHA optics is the hexagonal ice crystal. For CHA, we need plates rather than rods. Sunlight enters a vertical side (rectangular) face and exits the bottom (hexagonal) face.


Of course, the different colors in the sunlight are refracted by different amounts. The dispersion of colors is fairly wide in CHA.

For more images of this atmospheric grooviness, you can check out this filtered gallery, or image-search "circumhorizntal arc." (Remember that an image-search will give you many results that are incorrectly tagged.) My favorite CHA image is the "fire rainbow" photograph taken near the Idaho/Washington border some years ago. It caused enough of a stir to get its own Snopes article!


My travel shots and landscapes from the trip are here.

Sunday, July 25, 2010

AAPT Portland pics are posted

The AAPT's 2010 Summer Meeting in Portland was another sip from the fire hose. Much more to see and do than can be fit into the brief window of opportunity.

I used my new Fujifilm FinePix HS10 to grab a photo or two.

Most pics are from the High School Share-a-thon, the Gala Demo Show, and the Walking Tour of Portland.

2010 07 AAPT Portland Summer Meeting

Enjoy!

Tuesday, July 13, 2010

Creationists, GW denialists, truthers, birthers explained

When it comes to closely held beliefs, facts often don't matter. At all.

Research from The University of Michigan suggests that people generally cling to their personal beliefs despite facts that contradict those beliefs. Indeed, contradictory facts sometimes drive believers deeper into their unfounded beliefs. This is referred to as "backfire."

A recent column by John Trimmer eloquently described that "When science clashes with beliefs? Make science impotent."

One of my father's truisms was, "no one ever wins an argument." I hated that one when I was growing up because I loved to argue. To me it was intellectual sport, and I was better at debate than I was at kickball.

By high school, I knew my dad's wisdom was correct. But I justified my hobby another way. I knew I couldn't convince my opponent to change their mind. I argued for the sake of the bystanders. The pickup arguments in classrooms and hallways would often draw a small crowd of onlookers. They were not invested in the argument, so they didn't have to entrench. Their minds might have been open. It was the audience—not my opponent—I hoped to convince.

For other purposes however, the Michigan study reiterates the fact that arguing with a true believer bears no fruit. Often the believer is eager to argue. The act gives weight to their discredited theory.

And there simply is no factual evidence that will change their mind. None. Perhaps the best policy is to leave them by the side of the road as reality moves on. Let them wallow in their fairy tale as research moves forward. The only problem with that is that they populate school boards and state education commissions, where they can inculcate students far and wide.

At those organizational level fact-blind believers must be fought, lest your state becomes the next Texas or Kansas. But on a personal level, it's best to save your breath.

Thursday, July 08, 2010

The Amaz!ng Jump 2010

The Amazing Meeting 8 is coalescing. Attendees are arriving at the South Point. The Del Mar is filling with skeptics from around the world.

And I jumped out of a plane.



Beneath the jumpsuit? The Amaz!ng Jump 2010 T-shirt.

Sunday, June 27, 2010

Good solution or all wet?

From Britain's Orange:
A bus company in China has launched a new 'drive safely' campaign - by hanging big bowls of water next to their drivers.

The Longxiang Public Bus Company in Changsha, Hunan province, says drivers must drive gently to avoid spilling any water.

Bus drivers are expected to ensure the bowls are still full when they finish their shift, reports the Xiaoxiang Morning Post.

And the company warns drivers that CCTV footage will be studied to make sure they do not top up the bowls with water.

"Passengers often complain that sudden braking and bad driving makes them really uncomfortable on the buses," said a spokesman of the company.

"Hanging bowls of water in the driver's cab will discourage them from making any jolting starts, sudden braking or bad turns."
Is this a clever application of inertia and fluid dynamics? Or is it more show than go? (Notice the bowl is arranged as a pendulum rather than being fixed to the body of the bus. Curious.)

Friday, June 25, 2010

Equatorial star trails

Star trail shots are difficult to take but very groovy when they turn out well. I got one at Crater Lake years ago, and the current edition of Conceptual Physical Science Explorations has an awesome one on its cover. (Star trails over Mono Lake? It doesn't get any better than that.)

Or does it?

But I digress. Astrophotographer St├ęphane Guisard recently made this image.


It was taken at high altitude in Ecuador using a wide angle lens. Northern and southern hemisphere night skies race across the 10-hour exposure. Even a bright meteor gets in on the fun.

Hat tip: The Bad Astronomer

Tuesday, June 22, 2010

A fan with no blades?

That crafty James Dyson reveals the physics behind his Air Multiplier.

I hope it doesn't offend anyone's Bernoulli sensibilities.



I know: one more thing we didn't invent. Sigh. We're not Knights of the Realm, either.

TAM8 update

The Amaz!ng Meeting 8 (TAM8) is July 8-11 at the South Point Hotel Casino Spa in Las Vegas. My addiction precludes my absence. The organizers provided an update today, and warned of an impending sell-out. This Mighty Wurlitzer appears to be recession-proof, getting more popular even as the economy flounders.

There will likely be over 1000 in attendance. Fewer than 200 attended TAM1 in 2003. There are reasons for my addiction, but I've blathered on about them before.

But I will reiterate this: The conditions under which I won't attend TAM are
1. I am dead and/or
2. There is no TAM.
Otherwise I will be there.

Saturday, June 19, 2010

Fantasy Football viral videos are... fantasy!

So says Captain Disillusion. And he doesn't just say so, he shows how the video trickery was done.

He's quite good at this. See for yourself:



I look forward to seeing him soon at The Amaz!ng Meeting 8.

Sunday, June 06, 2010

To the Mentosmobile!

Those crazy science pranksters at EepyBird have done it again. This time, it's human propulsion from Coke Zero and Mentos. Take a look.



The video raises valid questions.

1. Is Coke Zero a superior propellant or a more lucrative product placement? Perhaps the answer is "yes." I ask because I do not know.

2. Something here is begging to be calculated, but I fear there are too many unknowns. Help me out, bloggees! Is there some reasonable way around the many unknowns?

3. Why is the vehicle braked from the start?

4. I don't understand all the design details, but were they hoping for a Newton's third law push from that wall? Or the transparent pistons? Was this really the best thrust design?

Fun to watch as always with these guys!

Saturday, June 05, 2010

PhET T-shirts

I designed and posted a couple of T-shirts via Zazzle. I designed them to show my love for PhET. Yes, I am a geek. (Further evidence of my geeky PhET affection was provided previously on The Blog of Phyz.)

PhET is The University of Colorado's Physics Education Technology program. They design, produce, maintain, and promote high-quality interactive science simulations. And they give the simulations away for free!

I bought a black tee to wear during our PhET days (between the last of the new content lessons and the beginning of final exams). The black PhET tee looks better than Zazzle's "model display" of it. (Click the shirt to get to its product page, then click the design tab to see a better rendering.)

I've got a copy of the Matrix design ordered.

Zazzle incorporates a royalties structure so product designers can share in the revenues. I'm donating anything the PhET products generate to PhET. Seems fair.

So go buy yourself a PhET shirt! You know you love PhET, you'll be the only one in your neighborhood with one, and it supports the PhET program.

College Board misses its own deadline

I don't have any reason to be optimistic about AP Physics B Redesign news in 2010.

I have heard about pending changes. Took part in a survey. Attended an AAPT meeting session devoted to the redesign. In Summer 2008. In Spring 2009, I blogged about the pending redesign.

In Fall 2009, the College Board rolled out a public page announcing that the redesign information, itself, would be available "in early 2010."

I felt safe that upon returning to that page in June 2010, I would see the promised info fully revealed. My hope was misplaced.

The page now promises,

"Additional information about the revisions to AP science courses and exams and the range of resources, including sample questions, that will be available to teachers to facilitate the integration of these changes into their courses will be announced in fall 2010."

Fall doesn't end until late December. By then the holiday season is upon us. And by then, the page may be updated to reflect that the details will be posted "by early 2011," which doesn't end until June one year from now.

I guess we'll get the information when the College Board actually releases it. Promise dates and timelines appear to bear no authority.

Ladies and gentlemen, The Paper Slinky

My friend, Carol, alerted me to this recent EepyBird gem, from the "creators" of the Mentos/Diet Coke demonstration. Enjoy.

EepyBird's Sticky Note experiment from Eepybird on Vimeo.

Sunday, May 30, 2010

Conceptual Physics PhET-based Tech Labs

There are some awkward time slots that arise at my school this time of year. We schedule final exams in a semi-staggered manner so that seniors are done with their final exams two days before undeclassmen.

So we have a senior finals schedule and an underclassmen finals schedule. They intersect on one day. Two of the three senior finals days are block days in which morning block senior classes have final exams, but afternoon blocks do not. Add to this the fact that physics and AP Physics are mixed-year classes, and you've got some good times!

I schedule the final exams in physics on the senior finals schedule. But that leaves me with two non-final block periods with all students and three non-final block periods with underclassmen only. All of this, of course, at the end of the school year, when students are focused on academics and performing at their best!

One solution to these "empty periods" is classroom cinema. But I don't like that idea so much. Still it's like pulling teeth to get some students engaged in robust, challenging physics work.

This year, I'm going to try the "Conceptual Physics PhET Variety Pack". I put together a collection of PhET-based Tech Labs for Pearson Addison Wesley's Conceptual Physics Laboratory Manual: Activities · Experiments · Demonstrations · Tech Labs. There are some we never got to try in class. So I ran copies of each, and will let students choose which ones they'd like to try. They'll count as lab points toward students' grades.

I posted a page with links to PDFs of the student labs, and to the corresponding PhET simulations.

Conceptual Physics PhET-based Tech Labs

There are tech labs for every part of Conceptual Physics: Mechanics, Properties of Matter, Heat, Sound, Electricity and Magnetism, Light, and Atomic and Nuclear Physics. And many PhET simulations are leveraged: Moving Man, My Solar System, Masses and Springs, Gas Properties, Electric Field Hockey, John Travoltage, Wave Interference, and Radioactive Dating Game. I'm working on one for The Photoelectric Effect, but I doubt it will see the light of day (!) before the school year is out.

Is that Alice Cooper I see waiting in the wings?

The List

I am sometimes accused of expressing OCD-like tendencies. I label lab equipment by group and store apparatus in an organized manner. I don't think I could function otherwise.

And I was a numismatist at an early age. That and philatelism are clear indicators of OCD predilections. I prefer to embrace my OCD rather than to deny it or apologize for it. I think of it instead as a hereditary gift from my grandmother, passed on to me through my mother.

Anyway, I made a list. A list I often thought to make, but never did. A list that some regard as a cry for help.

While listening to NPR's Weekend Edition Saturday a few weeks ago, I heard a story about the three American hikers detained in Iran. And the name of the fourth (undetained) hiker jumped out of my radio: Shon Meckfessel. I thought I had had a Shon Meckfessel in my physics class once upon a time. And how many Shon Meckfessels could there be in the world?

I dug around on the interwebs and in my own Excel spreadsheets (used for grading purposes), and found him. Turns out he was also the founding bassist for Sacramento's Cake, but moved on before they got big.

A week earlier, a coworker at Rio recounted a run-in with one of my former students. He presented a perfectly good description, including the first name (Jason), but was disappointed when I couldn't recall the particulars of this student. I pleaded that over the course of my career, I had taught over 3000 students, and fall short of having distinct memories of each of them that I can search with success on short notice.

So I finally made the list. Of the names of every student I've ever taught at Rio. All 3239 of them.

It was mostly a simple task. Copying and pasting lists from my Excel spreadsheets. But some went so far back that they cannot be opened by Excel anymore. That's right Microsoft fans, Excel 200x cannot open Excel 1.x files. Apparently I was supposed to have converted them back in the days of Excel 4.x and am forever hosed since I didn't do so. Microsoft offers no converters/translators. A friend was able to open them using high-tech trickery. But I also did a decent job of picking those names out from an old Tesoro (yearbook).

Now I can say, with a degree of confidence, that I have taught over 30 Jasons. And more than 60 Michaels. Neither of those names challenge the enduring popularity of Jennifer; I've taught more than 70. And what about Mary? I had two my first year ('86-'87), and five ever since. A 10:1 Jennifer to Mary ratio!

Onesies? Aanand, Ragashree, Karthikeyah, Sohini, Goodwin, Jori, and Lonicera, to be sure. But also Allen, Ann, Fred, Hank, Harry, Helen, Hilary, Irene, Janet, Joan, Lynne, Raymond, Seth, and Valerie. (Each name on the first list was flagged by the spell check. None on the second list were.)

When I ask friends/family/colleagues for the most popular family name, they strike out with guesses such as Smith, Jones, and the like. This is true even of those who work at my school! My own sense was correct: the most common family name has been Kim (26). But even Kim is eclipsed if you combine Lee, Li, and Ly (28). Indeed Lee/Li/Ly beats Smith and Jones combined.

I posted the list through the back windows of my classroom. I highlighted all current students in yellow. I highlighted students who are now teachers at Rio in blue. A handful of students find the list mesmerizing.

Likely just those with OCD.

Sunday, May 16, 2010

Greased Lightning - new PhET lab

I posted a new activity to PhET's website. It's based on their simulation, John Travoltage. The simulation explores triboelectric charging and spark discharging. The student controls one arm and one leg of an image of John Travolta. Rub his foot on the carpet and move his hand toward the doorknob, and a spark will jump. And John will express a vocal reaction.

Given the nature of the simulation, the title could only be Greased Lightning. The student worksheet and answer key are available for download.

Run it with students if you can work it in. If you like it, nominate it for a Gold Star!

Saturday, May 08, 2010

AAPT Summer Meeting in Portland: Workshop W18

Last year's AAPT Summer Meeting was held in my fair college town of Ann Arbor. I'm not sure what the Committee on Physics in High Schools did to offend the scheduling team, but the committee meeting was held at 7:15am. That's just wrong!

While brainstorming ideas for potential workshops to be run at the 2010 Portland Meeting, I posited one focused on the "weird days" at school: the first day of school, back-to-school night, and open house in particular.

The committee approved it and now I'm on the workshop schedule:
W18: What To Do About the First Day of School & Other Events. (Scroll down to W18.) It will be held Saturday, July 17, 1-5pm somewhere on campus at Portland State University.

I've worked out my own solutions to these potentially problematic special events and will share resources. But I'm also keen to learn of the solutions that others have worked out.

Looks like two physics teachers have already signed up for it. Hurry before the other 30 spaces are taken! Some workshops already have five signups as of this posting.

I'm looking forward to it. I've never hosted an AAPT meeting workshop, and it's always fun to spend time with other physics teachers talkin' shop.

Tuesday, April 20, 2010

Conceptual Physics Alive! Video Question Set

Now available from Arbor Scientific: the Conceptual Physics Alive! Video Question Set.

My school was able to purchase the entire set of Conceptual Physics Alive!, Paul Hewitt's Conceptual Physics course recorded during his tenure at The University of Hawaii, some years ago.

I enjoyed watching Hewitt grab and maintain his students' attentions with his enthusiastic presentations. But I never thought to show them to students. I show various episodes of The Mechanical Universe (high school and college) and Jearl Walker's Kinetic Karnival. But those videos were produced for television. Conceptual Physics Alive! was simply Hewitt giving physics lessons via lecture.

At some point, I needed to be out for two consecutive days and couldn't afford to waste the instructional time. I had a set of video questions (questions students answer during a video presentation) for an episode of Mechanical Universe. One day covered. But the second day? I produced a set of video questions for the appropriate episode of CPA, and I was good to go for the two-day absence.

When I returned, a student told me he preferred the Hewitt video to the Mechanical Universe. I contradicted him directly out of astonishment: "No you didn't! You preferred the Mechanical Universe because it's highly produced and has better graphics!"

The student insisted, "No, the bearded guy was more fun to watch."

Last summer I watched each of Hewitt's 34 video lessons and spent the time needed to produce video question sets for each episode. The process is fairly simple.

1. Watch the episode as a spectator. Simply take it in.

2. Grab a pencil and some blank paper. Watch a second time while working the remote control and listening for potential questions. Pause, stop, rewind. Write the questions as they come from the video. Include diagrams where it makes sense to do so. This step is messy. Some questions will be short-answer, some will be multiple choice, some will be true-false, and some will involve drawing or interpreting diagrams.

3. Turn off the TV and turn on the computer. Type the questions and draw the illustrations. If possible, create two forms (with as many different questions as is practicable).

That's how these video question sets came about.

Now I'm good to go for an absence any time of the year. Hewitt will be my guest lecturer, and I know my students will be engaged in his lessons.

The video question sets are the difference between me using the Hewitt videos or not. Now that I have them, I can use them whenever it makes sense to do so.

I'm very happy with the question sets for their variety and the fact that most lessons come with alternate sets. Students seated next to one another are to be given different forms. Keeps the wandering eyes to a minimum.

It was also important to me that the sheets look good: nice fonts and professional graphics. I think the pages look great and work great. I hope you'll agree.

Tuesday, April 06, 2010

ExploratoRio 2010 - ONE DAY ONLY!

Actually, all ExploratoRios are one day only, going back to the very first one in 1993. It's still a groovy, hands on experience of science and perception.

Here's a video from the 2001 event. (Sorry about the silent, black intro and outtro.)

Of course there are oodles of albums! Even some old, old thumbnails.

The Exploratorium is a continuing inspiration!

Rio Americano High School. Wednesday, 4/7/10, 7pm-9pm

UPDATE: A preliminary photo album is up!

Sunday, April 04, 2010

The Fountain of Fizz

Addison Wesley's forthcoming Conceptual Physics Laboratory Manual: Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird will include a demonstration lab write-up for the ever-popular soda pop geyser.

Here's some slow-motion video focused on the soda bottle. The clips are QuickTime, so you can download them to your own device (iPad?).

A write-up will appear in the upcoming lab manual. This copy is a PDF for your convenience. Oh, and the instructor's notes!

The Geyser Tube is a helpful device in this demo. It restricts the fluid flow for some Venturi fun. And it increases the likelihood you'll stay dry during the show.

Thursday, April 01, 2010

Power Balance Bracelet

A colleague at school is an accomplished runner and a world traveler. While in Spain, he learned of a "balance bracelet." For a mere €26 ($60-ish), he could purchase a bracelet which would purportedly improve his athletic performance. The bracelet includes a hologram which, according to promoters, "resonates at the frequency of the human energy field."

He asked me about it, because he knows I'm a skeptical type. Once I heard about the resonant hologram, I told him the bracelet was bunk. But I was intrigued, so I scoped it out. The demonstration is compelling!



Even more so with noted scientist and skeptic, Shaquille O'Neal.



But Richard Saunders' simple and effective debunk is almost too easy.



When working out and training, hard work and blood/sweat/tears are no longer required for athletic performance gains--when donning a bracelet can substitute for all that pain--I, too will be a world-class athlete.

Tuesday, March 30, 2010

Psychic FAIL

Like I say, where were the psychics on 9/10? And yes, the title of this post is redundant (or what I like to call a "double redundancy").

Saturday, March 13, 2010

GOODWIN LIU APPOINTED TO NINTH CIRCUIT

My first year of teaching (1986-87) was a blur while it was in progress. I was new to teaching, new to California, new to Sacramento, and new to Rio Americano High School.

But some things etched themselves into my memory. I had a number of excellent students. More than one who was smarter than me. I'm sure Jeremy Gollub knew physics better than I did. And he still does!

A few years ago, I started hearing Goodwin Liu on National Public Radio. Goodwin was one of my brightest students from that first year. So I wrote a post about it.

Now it seems he's caught the eye of President Obama. He's been nominated to serve on 9th US Circuit Court of Appeals.

Senator Jeff Sessions (R-AL) is not happy about the nomination.

Physics teacher Dean Baird (D-CA) is delighted. I hope to visit him when he eventually takes his place on the Supreme Court of the United States. If you don't know Goodwin, you'll think I'm getting ahead of myself.

Congratulations, Goodwin! I'm proud of you beyond what my words can convey!

UPDATE: Two blogs I know of that are tracking Goodwin Liu's progress as a nominee.
Confirm Goodwin Liu
Support Goodwin Liu

Facebook Group:
Confirm Goodwin Liu

Friday, March 12, 2010

Confirmed: No RTQs until budget turns around

There will be no 2010 revision of the Released Test Questions for the CST in Physics or any other subject.

The 2009 revision, which includes questions from operational forms used in 2003-2008, will be the last of the RTQs until the California state budget turns around.

I sent an online web form note to "Write STAR" and was pleasantly surprised by the promptness of the reply. (Jaded soul that I am.) I confess a degree of dislike for web form email generators: the sender (me) gets no record of the communication, and has no idea who the recipient will be. In the event it goes unanswered, you have no one to hold accountable and nothing to hold them accountable for.

Anyway, my inquiry was answered in a matter of hours. But it stated that the RTQ budget was cut last year and that there would be no RTQs until the state budget turned around.

I don't pretend to understand the details of the legislation mandating statewide testing, but I was always given the sense that releasing 25% of each year's operational form was required. Not a luxury reserved for when California was awash with money. Required.

If the money is so tight that the CDE can't desktop publish a PDF of used questions, think of the savings to be had by not producing an operational form filled with new questions. One that must be printed with ink real on real paper. Numbered, bundled, and administered. Scored and psychometrically analyzed. Performance-leveled and reported. State wide.

If the STAR program can't be run in accordance with the legislation, why is it being run at all? Dare I go out on the limb that says it has much to do with money and little (if anything) to do with teaching or learning.

Sunday, March 07, 2010

BMW ad: real or fake?

It's the tablecloth trick. But the cloth puller is not a magician or physics teacher. It's a motorcycle.



Objectors suggest the tablecloth in the XXXL stunt is sandwiched between the table and a table-sized plate of glass. The dinnerware rests safely atop the glass, and is never in any danger of being pulled off the table. I wonder if the objectors worked out the force that would be needed to free the cloth sandwiched that way.

Perhaps the stunt is real. And if so, who's to say that any "crotch rocket" with sufficient acceleration couldn't repeat the stunt?

Either way, it's recommended viewing when you cover the trick in class. Real or fake, the opportunity for discussion is rich.

ExploratoRio Snackbook: Overcoming Resistance

Here's a new entry to the ExploratoRio Science Snackbook, my homage to the Exploratorium's Science Snackbook.

Overcoming Resistance: Stretch the chain to see the light

The demo is simple and easy to arrange. And it links nicely to the nature of electrical resistance.

You connect a series circuit with a battery, bulb, and light-weight chain. When the chain is relaxed, the bulb lights dimly if at all. When the chain is stretched under tension, the bulb lights more brightly.

The snack write-up may undergo tweaks in the future. Suggestions are always welcome!

Bonus question. Suppose the chain were connected in parallel with the bulb. What difference--if any--would there be in the behavior of the bulb when the chain is stretched?

ETA: I'm such a slow-poke. Don Rathjen already wrote this thing up! With better pictures and details, too!

Thursday, March 04, 2010

This Too Shall Pass as a Rube Goldberg device

Your assignment: identify the energy transformations shown in this OK Go video. Repeated viewings may be required.

One thing that's often under-appreciated in such undertakings is the mechanics of the camera movement. Watch it again and imagine yourself as the camera operator.

ETA: This video has understandably gone "crazy viral." And many Scrutinizers Of The Web (and commenters on the YouTube page) have been clamoring to point out that the video was not shot in one take. "See the obvious edit at 2:28, etc."

To The Scrutinizers, I say
1. A+, good eye, nicely done, gold star and smiley face for the day...
2. Who ever said it was a single shot or one take? This point is somewhat important if we are to attach any merit to the "debunking" so ably accomplished by the Scrutinizers.

Here's what the video description claims:
"The video was filmed in a two story warehouse, in the Echo Park neighborhood of Los Angeles, CA. The "machine" was designed and built by the band, along with members of Syyn Labs ( http://syynlabs.com/ ) over the course of several months."

When I read that, I don't see a one-take claim.

I fear the Scrutinizers may have debunked something that was never bunk to begin with. If someone can direct me to OK Go's claim of a single shot/one take, please do. Otherwise enjoy the video and respect the creativity, cleverness, engineering, and energy that went into it!

ETA2: According to band member Damian Kulash, one of the flakiest elements of the machine was the marble table. Advice to future Rube Goldberg designers: put the flakiest stuff at the beginning of the sequence. Not at the end.

Wednesday, March 03, 2010

CST RTQs continue their backward March

Each year it seems, the California Department of Education's Content Standards Test Released Test Questions are allowed to mature for more than a year before being refreshed and replenished.

The dates for the most recent RTQ releases are
2003-2005: January 9, 2006
2003-2006: February 1, 2007
2003-2007: February 8, 2008
2003-2008: February 25, 2009
2003-2009: TBA

With the calendar stepping deeper into March, the CDE has reached a new slow. The CST legislation mandates the release of 25% of the previous year's operational form annually.

No doubt the mechanism by which the RTQ documents are produced has been hit by the ubiquitous budget cuts. That is to say, CDE's performance has been adversely affected by new limitations of resources. And when you claim your students' test scores suffered similarly because of budget cuts, everyone from your principal to Jack O'Connell will understand.

I'm confident that the 2003-2009 RTQs will appear before the administration of the 2010 CSTs. But I've been wrong before.

Saturday, February 27, 2010

How to start a brawl at the Physics Bar, Method #7

Refer to the changes in the speed and wavelength of a wave passing from one medium to another as "refraction."

And if you don't know why that will cause a brawl, you have no business in the Physics Bar!

Thursday, February 25, 2010

What kind of circuit is this?

I'm not sure what to call the circuit involving the chain of uninsulated Brainiacs in this clip. See 2:13-4:00.



Your ideas?

The segment from 4:00-4:53 is a nice example of a series circuit!

UPDATE: Commenters and NCNAAPT/PTSOS list responders have identified this as a resistance ladder or R-2R network. I love having access to the brainiacs of cyberspace!

Sunday, February 21, 2010

Torque on ice

Gunn High School physics teacher (and President of the NCNAAPT), Claudia Winkler, likes this "Physics at the Olympics"... moment!

Take a look:

Wednesday, February 17, 2010

Why does Glenn Beck hate science?

Glenn Beck recently trashed Bill Nye the Science Guy. Nye's crime? Other than being involved in science? An appearance on The Rachel Maddow Show. To make matters worse, Nye spoke truth about snowstorms and global warming. Clearly, Nye was begging to be put on Beck's Enemies List.

While Beck attempted to sell his typical twisted manipulations, Maddow wasn't buying. See for yourself.

Visit msnbc.com for breaking news, world news, and news about the economy

Tuesday, February 16, 2010

Check 2: Still no new RTQs

The 2010 RTQ release can no longer beat those of 2006, 2007, or 2008. If they drop before February 25, they can still beat 2009.

Raise your hand if you think that's going to happen.

That's what I thought.

See Check 1 for more.

Saturday, February 13, 2010

Adiabatic cooling puzzle

I'm a big fan of the PhET simulations.

But I'm puzzled by one aspect of the "Gas Properties" simulation.


If you open the simulation and squirt some gas (maybe 100 particles) into the chamber, the particles bounce around nicely. If you then compress the gas, the pressure and temperature increase as one might expect.

But reset it, squirt some gas in, and expand the chamber. The pressure drops, but the temperature remains the same. I was hoping for adiabatic cooling, but all I got was isothermal (and adiabatic!) expansion.

My thoughts? I want the temperature to drop: particles bouncing off a receding wall should recoil with reduced speed. And an expansion shouldn't be isothermal unless heat is added.

The good people at PhET assure me this is what's supposed to happen. But sometimes I'm just too thick to get it.

Educate me, experts!