November 04, 2014

I'm a little bit stuck - where did I go wrong?

I was asked by a colleague why the amplitude of tangential modes of a ring or cylinder scale as $$cos(m\theta)/m$$.

The answer was given by Rayleigh in his Theory of Sound, which you can read on The Internet Archive. Here's the relevant part:

The relevant solution to the differential equation (1) in Rayleigh for the tangential component has the  $$cos(m\theta)/m$$ behavior.

But, I wasn't able to start with Rayleigh's coordinates and end up with his equation (1).

Here's my work; where did I go wrong?

October 23, 2014

New Physics Drawings File: Springs

I added a new file to the Physics Drawings page. The file has my interpretation of stretched springs for use in physics homework, assessments, or presentations. All the files open in LibreOffice and compatible applications. They are CC licensed, so go nuts with using them.

August 02, 2014

AAPT Summer meeting twitter analytics #aaptsm14

The Summer meeting of AAPT 2014 has come and gone.  It was fantastic to get to engage with so many incredible teachers, to hear what they are doing in their classrooms, to catch up with old friends, and make some new ones.

The use of twitter at the AAPT conferences has grown over the past few years. Rhett had a post at the end of the 2013 Winter meeting in New Orleans which showed only 116 tweets using the conference hashtag.

This past meeting, there were over 1500 uses of the conference hashtag (#aaptsm14) according to Tweetarchivist. Using the tools from Tweetarchivist and checking some other analytics, I’m guessing that there were at least 42 users who used the conference hashtag to post to twitter not counting users who retweeted a post containing the hashtag.

75% of the tweets came from the top 25 users.  Who was the most prolific tweeter?  @LCTTA had 202 tweets (representing just over 13% of all tweets), compared to AAPT’s official account, which had a respectable 145 tweets (9.6%). Third place went to @rutherfordcasey with 97 tweets (6.4%).  The top 25 users are displayed below. There were a LOT of great tweets from many attendees (and many who were following from home). Check out some of these physics teachers and consider following them!

I made a word cloud of the most popular words used. By far the most popular word was “students” if I counted the twitter abbreviation “Ss”. Also “learning” was slightly more popular than “teaching”

What about the use of twitter through the week? The amount of tweets during the day took a dip in the middle of the conference, then were strong on the last day:

 Screenshot from Tweetarchivist
The most popular phone used to tweet was the iPhone (no idea what model). I’d love to give props to the attendees who were using either a Blackberry (2 tweets posted) or Windows Phone (1 tweet posted) but I have no idea which user was on that one.  The breakdown of clients is shown below. I combined the  iPad and iPhone results, although the iPhone posts dominated.

 iOS (all clients) 610 Tweetdeck 259 Android (all clients) 227 Web interface 152 Hootsuite 114 Other 148

Finally, for fun, I have the top mentions of users as well as the other popular hashtags used in posts also tagged with #aaptsm14 - The top users mentioned were @AAPTHQ with 118 mentions.  This makes sense, as there were many people tweeting questions at AAPT.  The next user with the most mentions was @rutherfordcasey, who was organizing many of the meet-ups as well as tweeting about great sessions he was in.  The popular hashtags used included #perc2014 and #modphys.

Top users by posts they made:

 Top Users COUNT LCTTA 202 AAPTHQ 145 rutherfordcasey 97 SciEdHenry 92 drmagoo 90 eigenadam 77 TRegPhysics 57 achmorrison 55 dyanlj 39 fnoschese 37 SteveMaier_ 30 distractons 26 MartaStoeckel 26 QuantumTweep 21 UniverseAndMore 20 SJDJ 19 OpenStax 18 MsPoodry 17 Cabertram92 16 ng_Holmes 16 arundquist 16 rjallain 15 danny_doucette 15 astronomatty 14 MnSTA1 13

Mentions of users in posts:

 Top Users COUNT @AAPTHQ 118 @rutherfordcasey 114 @EEtkina 65 @LCTTA 58 @SciEdHenry 54 @achmorrison 52 @eigenadam 43 @bohacekp 37 @TRegPhysics 33 @MartaStoeckel 31 @drmagoo 30 @dyanlj 28 @kellyoshea 22 @UniverseAndMore 22 @arundquist 21 @distractons 18 @MsPoodry 17 @chrisgoedde 17 @leetramp 17 @ng_Holmes 17 @MrBWysocki 17 @UMNews 16 @jossives 16 @sciencegeekgirl 13 @phyzman 13

Popular hashtags used along with #aaptsm14

 Hashtags COUNT #perc2014 38 #modphys 34 #physicsed 31 #ngss 15 #newbies 11 #scavengerhunt 11 #scied 10 #msum 8 #physics 6 #tweetup 6 #directmeasurementphysicsvideos 5 #shameless 5 #minneapolis 4 #dmvideo 4 #perc14 3 #gamedev 3 #dbir 3 #edcampmsmn 3 #umn 3 #arduino 3 #womeninstem 3 #math 3 #scaleup 3 #edtech 3 #starwars 3

August 01, 2014

Words matter (was What does "brick and mortar" make you think of?)

(Note: I posted a version of this originally on July 31, 2014. It was accidentally deleted, and I was unable to recover the original post. I rewrote the missing parts and added an epilogue at the end.)

The PERC conference kicked off with an interesting talk by Mike Dubson from CU Boulder. There is a great summary of the talk by Stephanie Chasteen over at her blog. The talk was about comparing a traditional large lecture-hall physics class to a MOOC of identical content.

I was struck, however, by the repeated use of the term "brick and mortar” to refer to the face-to-face course. To me, the terminology immediately invoked a business metaphor, with the student as a customer and the professor as a service provider.  I asked the presenter if that was an intentional choice of words, but I don't believe that my question was understood before he chose to move on. (Incidentally, I specifically remembered him using the word "customer" to refer to a student enrolled in the MOOC, but he claimed he did not use that word.)

The use of "brick and mortar" and "customer" to refer to a learning environment reminded me of the advertisement for a faculty position at a college that demanded the candidate be able to provide excellent customer service. David Perry wrote a series of posts on that which you can read about on his blog.

My take-away from Perry's articles was that the words we choose to use have an impact on how we act. If we believe education is more than a business transaction, then we must not use words which make it easier for administrators, students, other faculty, parents and the public to expect that sort of relationship with us.

Prof. Dubson had earlier in his talk stated his belief that education is the process by which our collective knowledge and understanding is passed down from generation to generation. At the end of his talk he concluded by telling us about the elementary school teacher who inspired in him a love for reading. He said that those types of teachers cannot be automated or replaced by a computer. His passionate love for great education was clear.

If the type of teacher that drives great education cannot be automated, then it certainly can't be reduced to a simple transactional relationship that words such as "brick and mortar" or "customer" cue us to think. Nor can the responsibility of passing down the world’s collective knowledge, understanding and culture be simply bought like a box tissues with a click of a button or a swipe of a credit card.

Words matter. We need to be intentional about using them.

Epilogue

I was privileged to be able to co-host a discussion session at PERC which was about how the physics education and physics education research community should be thinking about implementing what we called in the abstract “Competency-Based Assessment” but which goes by many names. I was honored that Eugenia Etkina (and so many other people!!) showed up for this discussion.

After listing many of the names by which the assessment strategy is called, I had intended to switch to the more familiar “Standards Based Grading” (SBG) name for our session. Prof. Etkina raised her hand and pointed out how we know that grades and grading causes stress for our students and is not at all what we want to emphasize. She pointed out that the standards are measured by assessments.

I saw immediately the parallel between what she was pointing out to me and what I had been asking the speaker on the day before. Words matter. Even if I don’t intend to use the term “standards based grading” with my students it will better form our thinking if we remind ourselves that we are intentionally taking the emphasis off of grading. In our session we immediately switched to using the term “Standards Based Assessment and Reporting” (SBAR) which I intend to use exclusively going forward.

Words matter. Changing our use of words can be done; we just have to be intentional about it.

April 21, 2014

Frustration and failure - things to capitalize on to facilitate learning

There's a great answer to the question on Quora: "Why do we get frustrated when learning something?"

There's much more to the answer on Quora. Hopefully you can see all of it if you click through.

April 17, 2014

Dynamically updated figures - real data! Looking for more.

There are a number of graphs that I like to use in astronomy class which are based on historical data.  Over the years, the graphs have become a bit dated and I needed to find new copies of them.  I then discovered that some of these are kept up-to-date online at all times.  Very cool!  Here's one that I discovered, but I'm really looking for more examples of these.

 http://solarscience.msfc.nasa.gov/images/bfly.gif

I really thought that I had more examples of these - images that are dynamically updated, but that the url for the image stays the same. Now I can't seem to find any more.  Anyone know of any others?

April 14, 2014

Thoughts on mindset vs. grit

A recent story on NPR caught my attention. The story is about schools teaching "grit" and whether or not it can be done. My introduction to the concept of grit came from a really great episode of This American Life from 2012. Even though grit is only mentioned by name twice in the episode, there was quite a bit of discussion on non-cognitive traits and their importance to learning. My interest in the episode is summed up best by this line:

"Non-cognitive traits like grit and self-control are even more important in college than in high school."

How best to encourage the best non-cognitive traits leading to success in college?  In the NPR piece, Alfie Kohn makes a great point: persistent people persist.

I'm a big believer in the Dweck model of mindsets: fixed vs. growth mindsets. I work to cultivate growth mindsets in my students. It's not easy. It would be great to add grit to my student's toolbox of tools to use for success in college. I watched Duckworth's TED talk hoping she would have some research to present that would be useful for me to use with my students. Here's her TED talk:

If you watched the talk, you may have noticed that the only research cited was Dweck's work on mindset! The talk is over a year old, so maybe there is new work on grit that I'm not aware of.

I spent a lot of time thinking about these questions over the last few weeks. How can mindset be such a solid concept and grit sound great but have easy criticisms?

Leave it to Dr. Tae to answer my questions in less than 140 characters:
Simple, right? There's nothing WRONG with encouraging grit. It's just not as effective as building the growth mindset. Thanks, Tae!