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Add to that the fact that the prism has been replaced by a tetrahedron.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!