Tuesday, July 31, 2018

Physics teacher conferees treated to a demo show par excellence

Images from the 2018 Summer Meeting Demo Show, July 31 at the Renaissance Hotel & Conference Center in Washington, DC. Show produced by AAPT's PIRA Team (ft. David Maiullo and Stan Micklavzina) in conjunction with the Bubble Magic of Tom Noddy.

2018 07 AAPTSM18 Demo Show
2018 07 AAPTSM18 Demo Show

Thursday, July 26, 2018

Vintage transformer

I've seen a meme going around recently that says,

"It's not hoarding if your sh!t is cool."

True. And this is the excuse I will give for keeping old vintage equipment that still demonstrates some physics. The same could be said for my father-in-law, a retired hospital mechanic that got to keep a lot of old equipment when it was replaced. He recently gave me a National Twin-Control Transformer, pictured below. It was used in the surgical wards to change the voltage of the lights (left dial) and cauterizing gun (right) from the 120 V wall outlet. I found a few more of these online for sale as interest pieces, luckily no one suggested actually plugging it in. There is an on/off dial at the top and what appear to be banana-type lead ports underneath each control.


The art deco style seem to be from the 1920s or early 1930s. The plastic shell is Bakelite, the first synthetic plastic for which the American Chemical Society named it a National Historic Chemical Landmark. One of its most common applications were casings like this for electric devices because it was very electrically resistant.

I took the front of the case off so that I could see the very large transformers inside. My father-in-law had cut the cord internally, just in case any students decided to get too curious. The transformer wire gauge is quite large and the whole mechanism quite heavy. I took it out to show some students but I'm concerned about some of the wrap components so it will probably be left sealed up in between demos.

It would be interesting to encase the transformer opened up so students could see it but it was safe from curious hands. Its a reminder that what we teach them is actually used for something and hopefully they are able to recognize similar components.

Monday, July 23, 2018

Representation matters in Physics

Some of the hesitance that our students have about studying science is this misconception that you can only "do science" if you're "smart enough." Humanizing those that pursue science and their path to a STEM job helps more students consider doing the same.  A Twitter account called @RealScientists has a new curator each week to share their particular corner of science with the world. They have a whole week to talk about their specific job, the path they took to get there, publications, unique and funny memories, what they wish everyone knew about their field, etc. Some hashtags have gone viral to show the human side of scientists like #PregnantintheField with which female scientists share pictures of themselves with baby bumps while carrying out field research. The universal #BadStockPhotosOfMyJob hashtag gets really funny when scientists get a hold of it.

While most of us recognize that people come in all different shapes, sizes, colors and backgrounds outwardly acknowledging it is important in your classroom. In a time when many are feeling less welcome in our own spaces (work, home, country, etc) it is vital that we actively work to recognize marginalized groups in our fields and help to lift their voices.

On June 4th a new Twitter account @500QueerSci was launched with the purpose of bringing awareness of LGBTQ+ people working in STEM related jobs during the annual Pride Month. Their goal was to reach 500 personal stories and by mid July were at 630 biographies. People can submit their abbreviated biographies, pictures and social media links to be added to the catalog. The full list is found on their companion website 500QueerScientists.com.

The resource is amazing and as many have said when they first tweet their own featured biographies  they wish such a thing had been available when they were young. It serves as a reminder to young LGBTQ+ people interested in science that they are not alone and that can be life changing.

I recently went back to the website hoping to find a search bar to type "physics" into so that I could have a list of many LGBTQ+ people with backgrounds or jobs in the fields  of physics. I could not find one so I tweeted at @500QueerSci and asked:


They responded that such a feature was in the works but in the meantime offered to find such profiles for me. Below are the names and links they provided:

  1. Chanda Prescod-Weinstein
  2. Izzy Jayasinghe
  3. Giampiero Mancinelli
  4. Axiel Yael Birenbaum
  5. Nicole Ackerman
  6. Tzula Propp
  7. Shawn Cole-Woods
  8. Kelsey Collier
  9. Carlos Arguelles
  10. Aidan Robson
  11. Ana Barbara Rodriquez Cavalcante
  12. Beck Strauss
  13. Kerstin Nordstrom
  14. Tessa Carver
  15. Christopher Aubin
  16. Robert Newberry
  17. Jost Migenda
  18. Andrew Princep
  19. John Barentine
  20. Mackenzie Warren
  21. Katie Mack
  22. Ashley Spindler
  23. JJ Eldridge
  24. Stephen Lawrence
  25. Alysa Obertas
  26. Nick Geitner
  27. Andrew Welsh
  28. Georgia Squyres
So I have a list, now what? I intend to use it. I've seen several lessons and activities in the last year promoting learning about diverse modern scientists, not just the "dead white guys" we find in our textbooks. Depending on your school and community's comfort level you could do a few things with such a list; and the same could be done for scientists of color and women. 
  • Whenever a particular field comes up in class, say astrophysicist, feature an LGBTQ+ person or person of color instead of whoever is at the top of a Google search list. 
  • "Profile a scientist" activities are already usually limited to exclude the few that everyone already knows about like Einstein or Curie or Tesla. If you're going to set restrictions for who they can't research you may find yourself just producing a list from which students have to choose. And look at that, you have a class set (or almost) of physics related names right up there! How convenient!
  • You can present the list in its entirety, or the full website, for students to explore st their own pace. You can lead a discussion or offer reflection time for students to think about the featured scientists' paths through education and the hardships they may have endured for being LGBTQ+, why their visibility is important, etc. 
  • Make posters of the featured physics related persona biographies to display in your classroom or school all year.
  • Feature an LGBTQ+, woman and/or person of color that is in the STEM field each week in your classroom. 
There are lots more things you could do to help expose your students to a more diverse world of STEM, but that should be a start! I encourage you to read through the biographies above and more to learn more about our very diverse and large STEM community. If you have any other fabulous lessons to share please let me know!

Edit: I was able to add a few more resources I could not find the first time around thanks to recent AAPT plenary Frank Nochese:

The hashtag #ActualLivingScientists is used by all kinds of, well, actual living scientists, to share information about their work and why its cool. Several teachers print out some of these profiles to make displays in their classrooms or around

Heather Waterman @WatermanPhysics makes a daily doodle on her board about a scientists from an underrepresented group. I have a minor in art and I still don't know if I could draw a scene every day that was this good!

Wednesday, July 18, 2018

Be careful with your parabolic mirror


Let's say you you were into making solar ovens. Let's say that you decided a few years ago to make the best solar oven ever. Further, let's stipulate that you saw a nearly meter-diameter Direct TV antenna on the side of the road. An idea happened. You rushed to the local plastics store and bought highly reflective Mylar and glued it to the antenna.

Your solar oven was pretty amazing. While the hot spot wasn't super small, it was hot. Really hot. It can pasteurize a liter of water in 15 minutes.

And now you work at the Exploratorium and you think that you might bring it to work for grins. If you forget it in the back of the your Outback face up on a sunny day near the solstice, well, it can melt the molding in a fairly impressive way. I think I was lucky that my car didn't catch on fire.



You might be wondering how I could make such a mistake? I had a lot to carry into the Exploratorium, and the mirror wouldn't fit on the cart. I planned on coming back in a few minutes, but I got busy doing something else, and it slipped my mind. Coming back in the afternoon, I sat in the driver seat and looked into the rear view mirror.

Uh oh.



If you want to make your own parabolic mirror, you can find some excellent instructions here.

Marc "Zeke" Kossover

Tuesday, July 03, 2018

Cell Phone Airbag Challenge

Videos and pictures of this airbag device have been circling the web the last few days:

While not available for production yet it is getting a lot of publicity, and rightly so. It is an ingenious design that appears to be effective and reusable. It got me thinking about Dan Burns and my Crash Cushion project. Students are asked to design a crash cushion for either a smart cart or a cart with an accelerometer on it to crash into. They are challenged to decrease the impact force as much as possible, something we hope they realize is accomplished by increasing the impact time. 

I want to assign this as an emergency sub assignment for students that can be done theoretically, no cracked screens needed. So I looked to see what other designs might already be out there and found this 2013 parody by Honda:

It is in Japanese and does not have subtitles but the engineering process is still evident in the parody video. The end product is a giant case for your phone which of course makes the phone impractical. I see the Honda version as where my students my start in the process and then the new spring loaded German design as where they might end, with lots of R&D in between.

I plan to start the activity by asking students what is necessary for an automatically deployed air bag for a dropped cell phone. They could work in pairs or groups and discuss the basics of the design criteria for a device that protects the dropped phone from breaking. I expect students to think about drop proof cases they may have seen commercially available that have enforced corners. Once they have made a list of the design needs groups/ pairs could share their individual lists to come up with a whole class list.

After their criteria has been established I would like to show students the original Honda parody video above. The original Honda video has been removed from their YouTube channel but the video is available on a few news sites. Since I can't find one with subtitles I'm not 100% sure its clean for the classroom but its probably safe since it was originally published on the official Honda page. Even on silent students can watch the video and observe his design process; it could be considered an advantage that they have to rely on the visual only and can't regurgitate anything they hear the engineer say. They will probably laugh at the final design but it will serve as a starting point for the next stage.

Before watching the video, or after, students can be given the shorter article about the parody video  that summarizes it and includes stills from the video. Ask students to discuss if the Honda Case N meets all aspects of their design criteria. If their class list was missing something about the phone case being of a practical size they will probably want to add it now. This should lead to a discuss about additional criteria they might want to add.

At this point you can ask students to actually start brainstorming an air bag device on paper. This may include some conjecture and may not hold up to questioning:
"There will be this bag that shoots out here..."
         "How will it shoot out?"
"Ummmm some kind of compressed gas..."
         "Where will that come from?"
"Uhhhh..."

And to an extent that is completely okay. Students aren't going to be able to build a workable model like they do with the Crash Cushions project. This activity is not even necessarily focused on the ideas of impulse either but more on reasonable design criteria

I found this article about the spring loaded German design and made a pdf to share with students. The original video can be shared as well, although it is in German. I plan to ask students what is most important to that design and if it meets all of their design criteria. Students can discuss differences in their design and the German spring loaded design, which of their own design criteria it does not meet, etc.

The viral German spring loaded design is expected to go to Kickstarter soon to crowd fund enough capital to begin production. You could continue the activity with students by asking them which of their own designs they would help crowd fund (before showing them the German design). After they see the German spring loaded design you could ask students if they support it enough to fund it as well, hypothetically of course.

While I plan for this to be a substitute activity it does require the sub to be capable of playing online video clips if your students do not have one-to-one devices like Chromebooks. My subs are not usually capable of operating my projector nor are we a one-to-one school so I don't know how likely I will be to implement this in the next school year. I've summarized everything, including questions I would ask students in this teacher guide for the activity.

I would love to hear any one else's ideas for extending this activity below.