Slow your roll

If you're not following Frank Noschese (@fnoschese) on Twitter, why even be a physics teacher with a Twitter account?

And if you get useful mileage out of constant velocity buggies (such as these from Arbor Scientific) but wish you had a convenient, reliable way to curb their enthusiasm, Frank tweets this:

These homemade battery spacers are amazing! Better than anything else I've tried (foil, paper clips, etc) to make a slow moving buggy.
* One flat-head machine screw (#6-32 x 2"))
* Two fender washers (1/8" x 1")
* Three #6-32 hex nuts#iteachphysics #modphys pic.twitter.com/r5gCvpSGJw

— Frank Noschese (@fnoschese) October 25, 2019

Which way is north? Not so fast...

It isn't where we left it.

Over the course of geologic time, magnetic north wanders like the oft-maligned "drunken sailor". And it reverses polarity on a not-entirely-stochastic basis. It seems the pole is on the move again—with faster than normal speed—and models will need to be updated to keep pace.

As Magnetic North Pole Zooms Toward Siberia, Scientists Update World Magnetic Model

The North Magnetic Pole Is Shifting East, Fast

Even in the era of GPS, Earth's magnetic field is still an important component in terrestrial navigation.

Normalize Science

Most people that know me realize I'm a "science nerd," probably more appropriately described as a "science enthusiast." This means I enjoy talking about, reading about and encouraging others to learn about science. Most science teachers I know are enthusiastic enough about their subjects that they randomly insert science into everyday conversations. Sometimes this is greeted with "Hey that's interesting! Thanks for sharing!" type comments. Other times our science related comments are met with awkward science and a change of subject. This happened several times over the holidays and I was struck by how unusual it seemed to be to "talk science."

At both the extended family Christmas Eve and our neighborhood New Years Eve party I shared our plans for a family trip to see the Great American Eclipse next August. It is common when this comes up to have to explain to an otherwise well educated adult what a solar eclipse is and how it happens. At each holiday party I asked kids not "How's school going?" but "What are you learning in science class this year?" When the horn a child was blowing at a party seemed too loud I broke out the decibel meter app on my phone and reminded a mechanic friend to wear hearing protection at work.

My active and conscious support of science for all also presents with gift exchanges. I try to buy science or educational gifts for our family and friends, which I sometimes have to explain after they open it. For instance, this year I gave an Airzooka, a favorite classroom demonstration, to a family member who had received mostly gift cards from the rest of the family. As a young teenage boy he is now "difficult to buy for" and "doesn't want toys." As this video explains the Airzooka pushes a pocket of air that can be felt across the room. As soon as I assembled it for him he began shooting air at others across the room, and soon adults of all ages were stealing it to play with it. They had never seen anything like it, all wanted to know where to buy it and wanted to hear how it worked. Of course I was happy to oblige them and explain the science of it and how I use it to model sound waves in class. Family and friends were surprised how fun the Airzooka and other gifts were since they knew they were science and education related. Somehow labeling them that way came with the assumption that they couldn't be fun or couldn't be for younger kids. We've also given a drinking bird, geodes to crack, a moon night light with lunar phases, a solar robot toy, and more.

Luckily, other friends and families asked what my kids' interests are or if I have any specific ideas for them. They received many science and educational toys this year and I'm happy to report they are loving them all so far. Their Nana gave them Code-A-Pillars which allows them to build a robot caterpillar by connecting segments with different instructions on each. It allows students to practice rudimentary programming and learn sequencing. GG (Great Grandma) got my six-year-old a special viewing planter that allows her to see the plant roots as they develop. And a good family friend obliged when I said she really wanted a toy metal detector and she happily pranced around the yard listening to it ping.

While many science teachers already talk with their friends and family about science or give the gift of science, I'd love to see such practiced by non-scientists as well. A common phrase these days is "We need to normalize [X, Y or Z]." One way to normalize science for all is to talk about it. When someone around you asks "Why did that happen?" or "I wonder if..." discuss it with them, even if you don't know the answer. Encourage the young ones around you to be interested in science, even if they "don't want to be scientists." People like to cook, even if they aren't chefs. They like to go for bike rides even if they don't have professional equipment. I would argue that science can be an interest or a hobby for everyone. All adults can dabble in science without having a degree in science and they can encourage every child around them to do the same. Coloring became a viral sensation and the hobby-du-jour; let's make science the thing to do this year.

The universe will end in one week—plan accordingly

Just a friendly reminder that The Mechanical Universe is scheduled to disappear from the Annenberg Learner web site / streaming host / purchase page after June 30.

A more complete version of this tale of woe can be found in a separate post. But if you hope to have continued access to these episodes, now is the time to act.

When heroism doesn't help

Our instincts as science teachers is to celebrate our rock stars of science. Physics teachers shine a spotlight on Galileo, Einstein, Newton, Faraday among others. We praise their discoveries and praise the advancements they made for our understanding of the universe. We want our students to consider individuals who invented calculus or connected electricity and magnetism as nearly as important as a Kardashian. Hope springs eternal.

We are not going to stop doing this. Nor are my selfies with Neil deGrasse Tyson and Bill Nye coming down any time soon. However,...

Researchers found that students perform better in science where they read stories about how famous scientists struggled rather than when they read stories about what those scientists achieved.

The story from Shankar Vedantham's "Hidden Brain" ran this morning on Morning Edition and can be found on NPR.org.



It is a rare person for whom math and physics are easy subjects. Those who have achieved great accomplishments in those fields are not necessarily fundamentally different from anyone else. What might set them apart is their response to the challenge. Many see a challenge and choose not to engage. They looked at the daunting obstacles and directed their mortal abilities toward overcoming them. They were not genetically predisposed toward genius. They saw the mystery and believed it could be unraveled.

Bowling ball video alternatives

Physics teachers have been using a bowling ball pendulum for a long time. Considered a "classic" it is used to demonstrate conservation of energy and has amazed physics students. Thanks to viral videos of "bowling ball pendulum fails" or "... gone wrong" many of our students have already seen this demo:

Even our own Physics Teachers SOS (PTSOS) workshops have demonstrated this and had mixed results.

For several years I did not have a set up in my classroom that I felt was safe enough for this demo. I found this clip from Brainiacs a suitable replacement for a long time:

I especially like the fact that they try to adjust for the loss of energy (great discussion of work) in a secondary experiment. Of course doing it yourself is always best, but if you can't, this is my favorite replacement.

After I made my new pendulum (more about that here), I was able to make some new videos. My English teacher neighbor was kind enough to assist. Although I should have given him some more initial instructions.

 In case they don't think its a big deal, here's a point of view version:

There are many, many more out there if one of these doesn't fit the bill for you!

Moon shadow

As noted in a post in 2014, most of the United States will be able to see a total solar eclipse in August 2017. That is all kinds of cool and lots more information will be available as the date gets closer. This is an incredible video of the eclipse shadow, something I had never seen focused on before, for the 2012 Total Solar Eclipse in Australia.

The Sweeping Shadow - Total Solar Eclipse, Nov 14 2012,The Granite, FNQ, Australia. 

from Colin Legg on Vimeo.

FLIR's next generation smartphone thermal camera

The Consumer Electronics Show (CES2015) was recently held, and vendors were pushing their latest and greatest gizmos.

This includes FLIR, whose FLIR One thermal camera case for iPhone 5/5S was discussed in a previous post.

The biggest complaints about FLIR One was that it was limited to the previous-generation iPhone. People with an iPhone 6 or an Android were left out of the thermal imaging party.

FLIR aims to address these concerns with their next generation FLIR One model. It's not a case, but an attachment.

Next Generation FLIR One (CES2015)

Groovy… but I won't show it in class

Except as a springboard to a discussion of "What did they do wrong this time?"

But it is groovy. The world's largest vacuum chamber is used to perform the a variation of age-old physics classic, "penny and feather" free fall experiment.

Brian Cox visits the world's biggest vacuum chamber - Human Universe: Episode 4 Preview - BBC Two



Here's a video clip that I do show in class: A hammer and a feather dropped on the Moon.

Feather & Hammer Drop on Moon



Brian Cox is many kinds of wonderful, but showing free fall in a vacuum chamber using high-speed (slow motion) video, alone, acts to deceive.

A common misconception among physics learners is that gravitational acceleration depends on atmospheric pressure. Things float in space because there's no air in space. There's no reason to think g in the giant vacuum chamber is 9.8 m/s². All video of free fall in the evacuated chamber is artificially slowed. We never see the vacuum chamber free fall in real time.

The lesson could be interpreted that things fall more slowly in a vacuum. On Earth as it is in Heaven. Or the Moon, at least.

Russian meteor info from Paul Doherty

Exploratorium guru, Paul Doherty, sent this to the PTSOS Yahoo Group this morning. Enjoy!

Here is some info I've scraped together on the Russian meteor.
I'm sure that the numbers will be revised but this will give you a start

Russian Meteor

Latest data

The meteor will probably be named Chebarkul after the lake where the largest fragment is believed to have landed.

The rock was 55 feet across, 17 m in diameter
mass 10,000 tons = 10^7 Kg (given the accuracy of this estimate it doesn't matter if we use english or metric tons)
energy release 500 Kilotons TNT about 30 Hiroshima bombs
entry speed 44,000 mph about 20,000 m/s
breakup at 20 km elevation, or 80,000 feet.

The biggest meteorite found so far is 7 mm across less than 1/4 inch, it was a chondrite meteorite

Scientists made great progress understanding stony meteoroid impacts with the earth's atmosphere tat the time when comet shoemaker Levy hit Jupiter. Stony meteoroids that are the size of the one in Russia or the even larger Tunguska event very quickly encounter thickening air at high mach number. The physical stress of the atmospheric pressure due to high velocity of the meteoroid causes the meteoroid to fracture. The multiple smaller fragments decellerate more quickly than the entire original object object with accompanying surface heating and continued fracturing into smaller pieces. (These small fragments remain cool in the center while the surface is incandescent.) The breakup deposits a great deal of kinetic energy into a shock wave.

Movies of the scientific modelling of the Tunguska event here
https://share.sandia.gov/news/resources/releases/2007/asteroid.html

and now the same researchers are applying their computer code to the Chebarkul meteoroid
http://www.abqjournal.com/main/2013/02/15/abqnewsseeker/sandia-labs-researcher-mark-boslough-to-model-russian-meteor.html

here is the abstract of the Tunguska event article.
http://www.sciencedirect.com/science/article/pii/S0734743X08001784

Here is an article I co-wrote about another recent near collision
http://www.sfsite.com/fsf/2008/pmpd0810.htm

FTL Neutrinos? Maybe not

Slow down, Einstein slayers. The old man may still stand tall.

It appears there may have been an error in the faster-than-light neutrino findings that set the media world spinning last September. This just in from AAAS' Science Magazine (Science Insider).

Error Undoes Faster-Than-Light Neutrino Results

Hat tip: Shane Trimmer.

Scheduled to appear on Global Physics Department

Global Physics Department is a group of high school and college physics educators who meet weekly online to discuss physics, physics learning, and physics teaching. GPD uses Elluminate Live which allows for audio, video, white board, and chat communication.

The live event each week begins at 9:30pm (ET) / 6:30pm (PT) and runs for about an hour.

Moderator/instigator, Andy Rundquist of Hamline University, kindly invited me to present and I've been scheduled for Wednesday, March 21. The recent discussion of Modeling Instruction here at The Blog of Phyz apparently brought me to the attention of a Department member. So we'll talk about that.

Sessions are recorded, so you can entertain yourself running through their archives. I've done that and sat in on a live session. (Live sessions are more fun since they are interactive.) The presentation environment, Elluminate Live, does not suffer from lack of stimuli.

Betrayed again!

An esteemed colleague, LaVerne Gonzales, offered me nuggets of wisdom while I was still very much a rookie. One of them was, "There are two kinds of computer users: those who have lost data, and those who will." I don't assume that the wisdom originated with him, but he was the vessel through which it was passed to me.

He was speaking of the importance of backing up one's computer files. Still a novel idea in the mid- to late-'80s, when personal computing was in its adolescence. I once had a backup regimen involving over 100 floppy disks, and Saturday morning was the scheduled time. Automated backup systems, such as TimeMachine, have since taken the drudgery out of long backup sessions

As a bemusedly graying veteran of computers and teaching, I add a corollary.

There are two kinds of computer users: those who have been betrayed, and those who will be.

My first taste of betrayal was with Silicon Beach Software's SuperPaint. SuperPaint was the initial design software used to develop The Book of Phyz c. 1988. But it seemed to get slower and buggier with each new release. By 1992, I had to jump ship to Deneba's Canvas. Canvas was once a Mac-only application. In 1992, it was tighter and nimbler than SuperPaint.

Back in the bad-old (pre-iPhone) days, software would sometimes originate on the Mac platform, become popular, get ported to Windows, then cease to be developed for Mac. And so it was with Canvas. ACDSee bought Deneba and killed off Canvas for Mac.

They recently introduced a Mac OS product intended to compete with Apple's Aperture and Adobe's Lightroom. I was moved to let them know exactly why no Mac user would knowingly choose to do business with them. The product is alive, but I know of no one who uses it.

But I have tons of curriculum material in Canvas X format with no viable alternative software available. As of Mac OS X 10.7 (Lion), Canvas X is dead. The pain of that harsh reality lies in the near future.

Another betrayal came in the form of a test-generating program called measureUP. By the time I bought into it, it had become LXR•Test. By the time LXR decided that the once Mac-only product would fare better as a PC-only product, I had developed an extensive bank of original test items. There was a long, slow, tedious process converting my old LXR items to ExamView.

ExamView seemed to be all the rage just a few years ago, when we adopting textbooks. But now ExamView is lagging behind on development for Lion.

Indeed, Mac OS X 10.7 Lion is a betrayal all its own. With it, a little internal code-gem known as Rosetta is dead. Rosetta allowed OS X software written in the early days of OS X to work on Intel-chipped Macs. By killing off Rosetta, Apple killed two of the programs central to my teaching: Canvas (also abandoned by ACDSee), and ExamView (Einstruction development status: undetermined).

And finally we have the betrayal which is the genesis of this post. Once upon a time, Apple embraced the growth of online activity. They sold a suite of online applications and services originally known as dotMac (.Mac) then renamed to MobileMe. I bought the product because its iDisk allowed me to host my website as if the directories and pages were mere folders and files on my desktop.

Years later, Apple's new toy is iCloud. In yet another of Apple's ham-fisted moves, everything MobileMe must die: MobileMe bad, iCloud good. So gone is iDisk and website hosting. Poof, as of June 30, 2012. Unlike with the end of the Mayan calendar, the end of this world is real.

I must now move my websites to a new home on the Internet. I own the domain name phyz.org through 2018 via Register.com. And I can make phyz.org point anywhere I like. But I need server space. For now, I'm giving Rage a try. (The name nicely reflects my mood.)

Webpages, PDFs, and other documents are slowly filing (!) into the new space. I keep all the website files on my computer, so uploading everything is a simple, though time-consuming matter.

As of June 30, 2012, all my pages whose URLs include "homepage.mac.com/" will go 404. If Rage pans out, the new URL detritus will be "marge.ragesw.com/~phyzorg/".

The thing to remember is that phyz.org and ptsos.org should always work. They'll redirect to new endpoints, but they should always get you there.

There's going to be much angst, confusion, wailing, and gnashing of teeth along the way. I hope it will be short-lived.

I haven't moved to Lion yet and will hold off on that as long as possible. I'll see if I can avoid use of iCloud, knowing that Apple is likely to wake up some morning and decide to shut it down. I have greater faith in DropBox at this point.

Then again, my track record for picking a long-term winner is not good. There simply aren't very many long-term winners in software to be had.

Discovery Days at AT&T Park

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