September 12, 2016

Day 11 - PHYS 201 and PHYS 110; A favorite physics puzzle

Last Thursday was Day 11 in Physics 201. We have wrapped up discussing vectors, so the next topic is projectile motion. To start this topic, we got out the ballistic cart apparatus and had the class investigate: traveling on a horizontal track vs. on an inclined track AND dropping the ball vs. launching the ball from the cart.

This is one of my favorite physics puzzles to explore in introductory physics. I heard at least two groups talk about how their trial "didn't work right" because the cart caught the ball when it was going down the incline.  So, they made the angle larger and then tried again - and again were surprised when the cart caught the ball. Great investigation technique here by the students - now we have to work on the analysis.

In Physics 110 we finished up talking about the first five conceptual objectives - including talking about homework questions and practice assessment questions. In terms of new material - we defined longitudinal and transverse motion of coupled oscillating systems. In the previous class we had the air table out (no photos) but this day we used the PhET simulation to explore coupled oscillators:

Normal Modes

Click to Run

We also got out the snaky springs to discuss basic wave behavior.  Working as pairs, the class explored the following ideas:
  • A wave pulse, showing the transfer of energy.
  • Reflection of wave pulses
  • Transverse vs. longitudinal
  • Frequency
  • Wavelength
  • Speed
  • Wave speed depends on the media.
  • Interference.
  • Standing waves.
  • Generation of harmonics.

September 07, 2016

Day 10 - PHYS 201

Today in Physics 201 we finished discussing all the TIPERs related to vectors.  One of the questions involved considering the orientation of the coordinate system.  We had good class discussions about that question.

Also, I shared my version of the "Problem Solving Process" including this poster hanging in the front of the room:

I guess it is clear that I'm not a graphical designer. ¯\_(ツ)_/¯

September 06, 2016

Day 9 - PHYS 201 and PHYS 110

What happened to Day 8?  I forgot and the Labor Day holiday happened, that's what. :/ (Last class was starting vectors, finishing the intro to coding, and doing the first assessment.)

Today in Physics 201 we started vectors in the 8:00 am section and got both sections going with the nTIPERs related to vectors.  I used the PhET simulation for vector addition to get the discussion going, then turned the class loose on the nTIPERs.

Here's one student's artwork with the sim:

I like it!

In the 10:00 am section we had a bit of time to discuss misconceptions from last weeks assessment.  I showed some photos of answers given by students on the assessment.  Surprisingly to me, the students self-identified their own work.  I hope the discussion was positive and productive.

In Physics 110 we looked at coupled oscillators, including getting out the air table for looking at pucks and springs coupled together.  We also finished the work with the IOlab devices and measuring the spring constant with them.  We finished up class by doing some end-of-chapter problems from the first two chapters. First assessment in this class will be next Tuesday.


August 31, 2016

Day 7 - PHYS 201

Today in Physics 201 the 8:00am section finished up the TST activities and then did some nTIPERs related to the 1-D motion.

In the 10:00am section we looked at python for the first time.  I stole material from Rhett Allain's introduction to coding - starting with the class looking at constant velocity and constant acceleration motion.  We used, which I think I'm going to stick with as long as possible.  Here's the code we started with:

One note - there was a bit of trouble running the code on the classroom laptops. I'm not sure if it is becuase we use Internet Explorer or because I chose to use GlowScript instead of straight python. I'll need to look at this more.

August 30, 2016

Day 6 - PHYS 201 and PHYS 110

Today in Physics 201 we continued with the TST activities from yesterday.  The 8:00am section started them, and the 10:00am section finished them.  In the 10:00am section we did a few more TIPERs after completing the lab activity.

In Physics 110 we looked at the data from the PhET simulation. Students were shown how to plot force vs. stretch distance. The goal I was heading for was developing the idea of a spring constant and Hooke's Law  I wanted to try to make the analysis more real to try to illustrate what we are trying to measure.  So I had this set up (thanks to our awesome lab prep staff!) in the lab:
Springs with identical hanging masses.
The springs all had the same masses hanging from them, thus the same force.  Students easily understood that the spring with the least amount of stretch was the hardest (in terms from the PhET simulation) and the spring with the largest stretch was the softest spring.  We will follow up on Thursday to see how the understanding is progressing.

Day 5 - PHYS 201

(Day late...oops.)

Today in Physics 201 we got the 8:00 am section caught up with the calculus-based derivations of the kinematic equations.  The 10:00 am section asked some questions from the homework which led right into the "Tools for Scientific Thinking" activities which involve students walking in front of the motion detectors.  We only do the first 3 of these activities.  With some encouragement and bit of pushing, most of the groups got through the first two activities in a little over an hour.

Students working on the "Tools for Scientific Thinking" activities.

A better way to give practice problems?

Is it better to do traditional physics problems...or would there be value in structuring problems so that the answer is stated in the problem?

For example, when I think of a "traditional" physics problem, I think of something that looks like this:
If air resistance is negligible, determine the maximum height (above its release point) of a ball that is thrown straight upward which is in the air for a total of 3.0 seconds. 
But, what if the problem were stated more like this:
Show that when air resistance is negligible, a ball thrown straight up that is in the air for 3.0 seconds reaches a maximum height of 11 meters above its release point.
In my mind, the second version explicitly puts emphasis on the process and the reasoning behind the process, whereas the traditional problem naturally emphasizes the answer to the question.  I can see this way being done in the classroom setting, for homework practice as well as assessment purposes.

What am I missing here?  Why isn't this done for intro physics classes?

August 29, 2016

Embedding PDFs in a LaTeX file

Have you ever wanted to embed a PDF inside a larger LaTeX document?  For my "Book of Infinite Learning" I wanted to embed a copy of two different journal articles.  I didn't want to just grab the text and redo the layout of the articles.

Fortunately, there is a LaTeX way to do this.  Here are the commands I used:
\includepdf[pages=-, fitpaper=true]{filename.pdf}
The heavy lifting is done by the \includepdf command from the pdfpages package.  Read up on the options for that command if you don't want to use all the pages in the file.

What really made my day was the ability to change the margins for my LaTeX document for just the PDFs I wanted to embed.  Using \newgeometry I can specify smaller margins for these pages, since the PDF already has plenty of margin spacing.  Then \restoregeometry reverts back to the document margins.

I'm very happy with how this turned out.

August 26, 2016

Do you know about booklet printing?

I need to make a confession. I may have a problem.

I'm addicted to booklet printing. 


Last Spring at the start of the term I was fretting about whether to give paper copies of my syllabus or stick only with the online version. 

I may be kidding myself, but I am trying to use a well-formatted layout for the syllabus so that it is easy and welcoming to read. I know not all students will read it, but I want to remove as many barriers as possible. 

The real issue was the page count. I had 80 students and an 8-page syllabus to hand out. Even double-sided, that's a lot. 

Enter booklet printing. 

It's an option on Adobe Acrobat to print foldable booklets. That puts four pages on a single sheet of paper. What's that? You don't want to hand out super small booklets made on standard sheets of paper? Print on legal paper - then each page is 8.5" by 7". 

I do TIPER packets this way and other random handouts that I create for my classes. Now practically everything is booklet printed. We save paper and the multiple sheets are easier to keep together. 

What do you booklet print?