Sunday, August 11, 2019

Syllabus alternatives

In the last few years I've tried to reflect more on why I do certain things and what the students get out of each. Starting my 14th year I now have way more resources than I can fit in a year and can pick and choose what I want. I am making myself justify each activity, and "because we always have," doesn't cut it. At the start of the year one year I thought about my class syllabus and what I expected students to get out of it versus what my students actually did. I saw it as an important resource of information, a contract between us about how the class would be run with each of us holding up our part of it. My students, and arguably the adults in their lives, saw it as a box to check by signing it without reading it. Students would ask me all year questions that could be answered by reading the syllabus, I would find the copies they were supposed to keep all year on the floor in the first few weeks. So my syllabus was not being read, so it was not working as it was. So I changed it, two different ways for two different classes.

First, I changed my Physics syllabus from two pages of text into a visual syllabus (like an infographic). I loved the one page result that I made using Adobe Photoshop, even printed in black and white students found it much easier to digest.
A few friends wanted their own versions (above left) but I had to edit it for them because they didn't have the software.  This year I rebuilt it in powerpoint (above right) for my Conceptual Physics which makes it much easier to share. It's available here as a pdf so you can see how it turns out and a powerpoint file so you can edit it if you want.

For creating your own I have a few suggestions:
- Use pictures to represent what you can like the book cover and the calculator near the top.
- If you can represent it in a graph, do it!
- Be brief! Try highlighting the important words in your syllabus and see what little is left.

This version is still a paper, that requires a signature and should be kept all year. I retained this part of the traditional approach for my Conceptual Physics students because they will have a notebook in which they keep all their class materials and it will be glued in. For regular physics, as they are older, I will probably not do a printed version again.

When I began teaching AP Physics C and had to draft a new syllabus I again focused on what I needed and why. I wanted my students to read my syllabus as their was important information about the outline of the course. I wanted them to have access to the syllabus to read later but they did not have to necessarily keep the paper. So I decided to make a Google form that had paragraphs from my syllabus interspersed with comprehension questions for my students to answer. I made a similar version for parents with fewer questions and aligned more to things that might concern them more (like the A-/B+ border). The full text version of the syllabus is also posted on Google classroom so my students can access it anytime.

This will be my third year using the digital syllabus in AP and I love it. The students complete it sooner (I can even email it to them the weekend before school starts) and it takes care of a lot of questions because they actually ready it. When our school is completely one-to-one I will probably do a digital syllabus for all my classes but will probably use images like the visual syllabus instead of paragraphs in between.

Friday, August 09, 2019

The evolution of color vision in tetrachromats

Many of us have a sense of color-mixing among trichromats. There's this classic image of the primary and secondary colors of light achieved by overlapping monochromatic circles of primary colors.

We overlap the red, green, and blue in a triangle to produce magenta (red + blue), cyan (blue + green), yellow (green + red), and white (red + blue + green). We have three distinct cone receptors in our retinas, sensitive to red, green, and blue. So this all makes good sense.

But birds have four cones and can seen into the ultraviolet. Researchers say this gives them an additional dimension of color vision. Imagine red + ultraviolet. You can't: we don't have a name for that mixture, nor can we visualize it. A color mix square would be called for. Actually, that wouldn't work.

Seems the number of possible color-mixing outcomes is 2^n – 1, where n is the number of primary colors. Three primary colors yields 2^3 – 1 = 7 outcomes (R, G, B, M, C, Y, W). Then four primary colors produces 15 outcomes. But the color mixing square can only accommodate 13. How unfortunate. Downright unlucky!

Here's what I got when I tried to populate the cells of a color mixing square. D-oh! Now I'm getting why an extra dimension of color is called for here.

For many more details and implications, check out the Science Friday segment below.

When I say I'm a big fan of SciFri and appreciate the science communication work that host Ira Flatow does, you might suspect a "but" is sure to follow. Who am I to disappoint?

Listen again to the minute from 13:15 to 14:15. I cringed when I heard this over the air the first time through. Ladies, has this ever happened to you? Maybe it was the result of multitasking on Ira's part, but I'm reticent to make excuses for him here. In any case: awkward. The guests maintained composure, so good for them. Still though... I hope I'm never that guy (but I probably have been).

Thursday, July 25, 2019

The Mechanical Universe High School Adaptations

The original episodes of The Mechanical Universe once streamed from the Annenberg Learner website and were available for purchase there. That changed and it seemed like they would be lost forever. But then CalTech posted them, so it seems all is well.

But the High School Adaptations followed a different path. They were available for purchase for years (VHS and then DVD) from Intelecom. But any and all distribution ceased years ago, and these pared down and reworked videos seem to have been lost to the mists of history. You cannot buy them and you cannot stream them.

So I decided to post them as "unlisted" videos on my YouTube channel. Two copyright claims popped up when I uploaded them. In "Introduction to Waves," someone owns the license to The Marriage of Figaro music that plays in the episode, so that episode is subject to ads that would benefit the license holder. In "Navigating in Space," a minute or so of Voyager Grand Tour animation is owned by the BBC. Inclusion of that minute would block the video from running, so I removed the offending content and tried again. No block; no strike!

Links to all 28 High School Adaptation episodes can be found at the bottom of this page:
The Mechanical Universe of Phyz

And now that they stream, they make for nice YouTube homework assignments! This frees up classroom time for other activities.

I feel awkward posting these videos since they don't really belong to me. I have not been asked by any license-holding stakeholder to cease or desist. At this point, they may be covered by Fair Use. I honestly don't know. It is certainly not my intent to infringe on anyone's copyright.

Here's an old favorite:

The Law of Inertia

Monday, July 15, 2019

Today in "What not to buy"

This floated through my social media feed today...

The comments were appropriately brutal. And it wasn't the anthropomorphization that the commentariat was ruffled about. I suppose that's a risk inherent to advertising on social media. Your sponsored posts are subject to comments. At least they are for now. Facebook, Twitter, et al will no doubt figure out how to fix that so as to reap even greater profits. And why wouldn't they?

In any case, you could certainly acquire one just so that your students could rightly lambaste you during your lessons on circuits, if you're into that sort of thing. By the way, will we even be teaching circuits outside of AP and IB in the NGSS future? I don't see it in the high school physical science DCIs. But I could be wrong. Again, I digress.

Rather than supporting this electronic transgression with my hard-earned money, I downloaded an image or two of the offending item and will add it to the things we talk about when we talk about circuits in class.

But if you're keen to buy, here's the link: Science - You Complete Me

The Blog of Phyz is not responsible for short circuits, burns, or fires that may result from the use of this product.

Friday, July 12, 2019

Adhesion Cohesion Lens-hesion

The correct reaction here is "I saw that when she posted it" because you subscribed to Physics Girl's YouTube channel ages ago. If not, proceed.

This Weird Straw Effect | EVERYDAY MYSTERIES

This seems to beg for further investigation using different liquids. Cooking oil? Corn syrup?  The interplay of adhesion and cohesion is central here.

It's fun to think about the extremes:

1. How would this have turned out if the liquid had maximum cohesion and minimal adhesion?

2. How would this have turned out if the liquid had minimal cohesion and maximum adhesion?

There are more questions that might be nice, too. If you think of a question (or a liquid), drop it into the comments.

Tuesday, July 09, 2019

Breakthrough: The Ideas that Changed the World

The Next Generation Science Standards place a new importance on engineering. There will be initiatives and ideas for how to engage students in designing and building things in class.

If we want to enmesh engineering into the fabric of our curriculum, we might want to consider shining a spotlight on the engineering history a few key inventions. The PBS series, Breakthrough: The Ideas the Changed the World shines that light on six such triumphs of engineering. The series played on PBS this past spring It streams on Amazon Prime. And the DVD set of the series, hosted by Patrick Stewart, is now available. Here's a rundown of the episodes.

The Telescope
Episode 1 tells the story of the development of the telescope, from a stone-age observatory to the space-based telescopes of the future.

It entails long-abandoned Stone Age dolmens once used as celestial calendars,
how Venetians made glass transparent, the optics of a medieval Persian camera obscura, a Dutch lens maker’s wartime breakthrough and a Venetian math teacher’s advancement of it, a Parisian invention improved by a spilled bottle of mercury, a team of women known as human computers who were armed with fly spankers, an athlete-turned-astronomer working high above Los Angeles, and telescope in space that will allow us to see as far as physics will allow.

Episode 1 "breakthrough celebrities" include Galileo Galilei, Edwin Hubble, Henrietta Swan Leavitt, Louis Daguerre, Hans Lippershey, and Ibn al-Haytham.

The Airplane
Episode 2 tells the story of the development of the airplane, from early human-powered attempts to the jet concepts of the future.

It involves a ninth-century moorish daredevil’s first attempt at human flight, how we had tails before we had wings, an artist obsessed with anatomy and flight, a whirling arm in the stairwell of a seaside mansion, the rubber band’s role in flight, the curve of a stork's wing, a connection to maritime technology and the gyroscope, the use of a deep-sea diving suit to fly high, why modern pilots are pressure tested, and the surprising efficiency of the jet propulsion gas turbine.

Episode 2 "breakthrough celebrities" include Leonardo da Vinci, Wilbur Wright, Orville Wright, George Cayley, James Doolittle, Wiley Post, Frank Whittle, Elmer Sperry, Lawrence Sperry, Otto Lilienthal, Alphonse Penaud, and Ibn Firnas.

The Robot
In episode 3, Locutus of Borg tells the story of the development of the robot. Well, Patrick Stewart is the series narrator, so... close enough!

It involves the ancient legend of Hephaestus and rudimentary Greek automatons,
a device that could learn a new tune and repeat it exactly, a desire to produce navigation tables by steam, the linguistic contribution of a Slavic cubist painter, the breakthrough of storage for programs, an imitation game, an electronic tortoise, a mission to Mars, a nuclear disaster in Japan, and the challenges of balance and hands.

Episode 3 "breakthrough celebrities" include Alan Turing, Charles Babbage, Ada Lovelace, Hero of Alexandria, William Grey Walter, The Banû Mûsâ brothers.

The Car
Episode 4 tells the story of the development of the car, from ancient sleds powered by primitive dogs to autonomous vehicles powered by graphene batteries. Gary Numan was not available for the narration, so Patrick Stewart handled the voice-over.

It involves ancient arctic sled dogs, the pairing the axle to the wheel, the smelting of metals from rocks, the spreading of a language, the need to pump water out of mines, the boring of naval canons, a stunt carried out by an inventor’s wife, the efficiencies of a slaughterhouse, and the promise of graphene.

Episode 4 "breakthrough celebrities" include Henry Ford, Karl Benz, Bertha Benz, James Watt, Thomas Edison, John Wilkinson, Thomas Newcomen, and Jay Leno.

The Rocket
Episode 5 tells the story of the development of the rocket, from ancient guano-powered fireworks to plasma rockets with magnetic confinement. 

It involves the use of bat guano from Chinese caves to drive off evil spirits, a modern-day celebratory rocket battle in Greece, a work of fiction by a famous astronomer, an imaginative tale about a trip to the moon, a visionary living in rural Russia, a breakthrough in dairy processing technology, a loophole in an international treaty, a repurposing of firefighting equipment, internal Soviet geopolitical subterfuge that stoked the Space Race, and plasma engines that could transport humanity to other worlds.

Episode 5 "breakthrough celebrities" include Robert Goddard,  Werner Von Braun, 
Konstantin Tsiolkovsky,  Jules Verne,  Ti Tian,  Sergei Korolov, Karl Gustav, Thomas Harriot, and Johannes Kepler.

The Smartphone
Episode 6 tells the story of the development of the smartphone, from the fall of Carthage to brain-interfaced apps of the future.

It involves ancient Roman battlefield communications, a painter-turned-inventor who devised a code still in use today, a groundbreaking technology whose rightful inventor had to be settled by the US Supreme Court, an obsessive inventor who found treasure in another scientist’s trash, a quirky keyboard talking machine, a Hollywood starlet who was also a prolific inventor keen to defeat the Nazis, the miniaturization of a circuit invented by an engineer who hadn’t yet earned vacation time, and a father eager to share a photograph of his newborn daughter with friends and family.

Episode 6 "breakthrough celebrities" include Alexander Graham Bell, Samuel Morse, Guglielmo Marconi, Hedy LaMarr, George Antheil, Jack Kilby, Polybius, Philippe Kahn, Homer Dudley, and Elisha Gray.

I produced companion question sets for each episode. They can be found at The Lessons of Phyz at Teachers Pay Teachers: Breakthrough—The Ideas the Changed the World.

Thursday, June 27, 2019

AP Physics C new Manual Part 2

This is a continuation of the original post discussing the changes/tweaks to the AP Physics C Mechanics curriculum by the College Board.

The Electricity & Magnetism curriculum is in the same new format as the Mechanics one. There are the same four Big Ideas that are across all the units:

Unit 1:Electrostatics
Unit 2: Conductors, Capacitors, Dielectrics
Unit 3: Electric Circuits
Unit 4: Magnetic Fields
Unit 5: Electromagnetism
Big Idea 1: Change (CHA)
Interactions produce changes in motion.


Big Idea 1: Force Interactions (INT) Forces characterize interactions between objects or systems.

Big Idea 3: Fields (FLD) Fields predict and describe interactions.
Big Idea 4: Conservation (CON) Conservation laws constrain interactions

With only five units instead of the seven  in Mechanics each unit contains more Leaving Objectives but I found the Essential Knowledge section a bit more sparse. There seemed to be more times that the equation was thrown down and then "using calculus" was meant to explain more of the content. I mean, it does, but I think the content needed under Essential Knowledge is more apparent in Mechanics than in E&M. Unlike in  Mechanics I don't recall seeing any additional equations not on the supplied equation sheet either.

Unit 1: Electrostatics (pdf or Google Doc)
Unit 2: Conductors, Capacitors, Dielectrics (pdf or Google Doc)
Unit 3: Electric Circuits (pdf or Google Doc)
Unit 4: Magnetic Fields (pdf or Google Doc)
Unit 5: Electromagnetism (pdf or Google Doc)

Wednesday, June 19, 2019

The Light Playlist of Phyz

Somewhere in the end-of-the-year rush, I failed to post the ever-important Light Playlist, suitable for background play during light and optics labs. I apologize for my tardiness in this matter.

Previously posted playlists: Waves & Sound, Magnetism, and Electricity. There's a "playlist" topic link below and to the right as well.

The Light Playlist of Phyz
And the LightSupertramp1997
Blinded by the LightManfred Mann's Earth Band1976
Calling AmericaElectric Light Orchestra1986
ColorsAmos Lee2005
Eye in the SkyAlan Parsons Project1982
Green LightLorde2017
LightSan Holo2017
LightSleeping At Last2013
Light (feat. Little Dragon)ODESZA2014
Lights Down Low (feat. gnash)MAX2016
New LightJohn Mayer2018
On the RadioDonna Summer1979
On the RadioThe Concretes2013
On the RadioRegina Spektor2007
RadioSixpence None the Richer2012
Radio CityEilen Jewell2011
Radio GagaQueen1984
Radio SongR.E.M.1991
ShadowAshlee Simpson2004
ShadowBritney Spears2003
ShadowColbie Caillat2011
ShadowJeremy Riddle2017
ShadowSam Tsui2013
ShadowStick Figure2015
ShadowWild Nothing2012
Shadow (feat. Trevor Young)SOJA2014
Sound and ColorAlabama Shakes2015
Spirit of the RadioRush1979
The Lights Go DownElectric Light Orchestra1981
Ultraviolet (Light My Way)U21992
Video Killed the Radio StarThe Buggles1979
Voice on the RadioMaríe Digby2008
WaveJustin Timberlake2018

Tuesday, June 18, 2019

The best laid plans

It's true: I see the world in physics. You might, too. So when I saw a thing at Panera Bread, I spun it into a narrative that's too good to verify. Meaning I could have it a bit wrong, but it feels right. It's 2019, so... good enough.

In any case, here's the observation: an LCD screen in portrait orientation goes dark when viewed through polarized sunglasses. Unless you tilt your head sideways!

My story is that the LCD was manufactured to be used in landscape orientation, as is the case for 99.9% of such displays. In that orientation, the polarization inherent in LCDs was set to be viewable even through polarized sunglasses. But the Panera queue application required portrait mode. Hence the trouble.

And honestly, if you're indoors at Panera, why are you wearing your sunglasses? (Actually, if they're prescription, keeping them on while waiting for your coffee might not be so unreasonable.)

Note that your modern smartphone can be viewed in portrait or landscape through polarized sunglasses. Their displays have been depolarized! Some kind of sorcery is at work here.

Tuesday, June 11, 2019

AP Physics C new manual

The College Board has redesigned (or tweaked?) the AP Physics C Mechanics and Electricity & Magnetism exams for the 2019-2020 school year. The instructors have access to the Course and Exam Description which has been expanded greatly. The 2014 version was 69 pages for both Mechanics and Electricity & Magnetism. The new versions are 174 and 170 pages each, respectively. Going through them is part of my summer plans (exciting I know) and I wanted to share my first impressions, resources, etc.

First of all, the organization is way different. The old version had a few pages on lab and course suggestions (you need money for lab supplies, the class takes lots of time, etc.) and gave a breakdown of the percentage of the exam by topic. Then came several pages of an outline of objectives of the "Students show understand/be able to..." variety. I had retyped these for my students and passed them out at the beginning of each unit. I thought it was important for students to see exactly what could be asked of them on the exam and also what was outside the scope.

Here are the old versions if you're interested:
A. Kinematics
B. Newton's laws of motion
C. Work, Energy, Power
D. Momentum
E. Circular Motion and Rotation
F. Oscillations  & Gravitation

The new version has a lot more information about the logistics of teaching the course. There is suggested pacing, although the range for each unit is large because they recognize that AP Physics C can be taught as a one year or two year course. The course is organized into 7 units, essentially the same topic breakdown as above. Within each unit are subtopics listings with learning objectives under each. Each subtopic has a Enduring Understanding statement which is defined as "long-term takeaways related to the big ideas that leave a lasting impression on students." Each Enduring Understanding comes with Learning Objectives and Essential Knowledge statements. The Learning Objectives have the same purpose as the old ones, the Essential Knowledge is more like a summary or clarification statement. These list the equations that represent the relationships described in the Learning Objectives, some of which are on the equation sheet while some are not. Each unit has a different amount of Topics and Learning Objectives. Some concepts seem to have more emphasis than they used to, for example resistive (drag) forces Under Unit 2 Newton's Laws of motion.

The lab related objectives have also been updated to be Science Practices, a list of skills related to both physical lab skills and also critical thinking and problem solving. There is a whole table that outlines the 7 main practices and the skills required for each. I plan to make a copy of it for my students. The old lab objectives were not as detailed, as a comparison:

Old practices:
3. Analyze data - Students should understand how to analyze data, so they can:
a) Display data in graphical or tabular form.
b) Fit lines and curves to data points in graphs.
c) Perform calculations with data.

d) Make extrapolations and interpolations from data.

New practices:
Practice 4: Data Analysis
Analyze quantitative data represented in graphs.
4.A Identify and describe patterns and trends in data or a graph.
4.B Demonstrate consistency between different graphical representations of the same physical situation.
4.C Linearize data and/or determine a best fit line or curve.
4.D Select relevant features of a graph to describe a physical situation or solve problems.

4.E Explain how the data or graph illustrates a physics principle, process, concept or theory.

Across all 7 units are four "Big Ideas" that remind me of the Cross Cutting Concepts of NGSS. The Learning Objectives for each unit's subtopic fit under one of these Big Ideas. A handy table is included:

Unit 1: Kinematics
Unit 2: Newton's Laws of Motion
Unit 3: Work, energy, power
Unit 4: Systems of particles, linear momentum
Unit 5: Circular motion and rotation
Unit 6: Oscillations
Unit 7: Gravitation
Big Idea 1: Change (CHA)
Interactions produce changes in motion.


Big Idea 1: Force Interactions (INT) Forces characterize interactions between objects or systems.


Big Idea 3: Fields (FLD) Fields predict and describe interactions.

Big Idea 4: Conservation (CON) Conservation laws constrain interactions



Overall the unit outlines and supplemental materials looks well designed and flushed out. There are reminders everywhere to view the online materials available for teachers and students. Students will have access to online practice multiple choice and free response questions that are similar in style to the AP exam. It is suggested that you assign these practice problems for homework but specifically states that it should not be graded other than for participation points. There is a page of sample instructional activities, notes space and more. All like the ideal unit outlines we were supposed to learn to make after the credential program. 

All in all I like the addition of information. The layout and new terms will take some getting used to and I'm still deciding what to give my students. I typed up each unit's topic, Enduring Understanding, Learning Objectives and Essential Knowledge for Mechanics. That... took awhile. On one hand I like the Essential Knowledge as background information for my students but I also worry it is too much detail for them and they won't look at it. I typed up the Science Practices (lab skills) and also separated the Learning Objectives into a separate document. And since I typed it up, you won't have to! I'll get to E&M later and I'll be sure to post it here as well. 

All Learning Objects (pdf or Google doc)
Science Practices (pdf or Google doc)
Unit 1: Kinematics (pdf or Google doc)
Unit 2: Newton's Laws of Motion (pdf or Google doc) and Circular Motion (pdf or Google doc)
Unit 3:Work, Energy and Power (pdf or Google doc)
Unit 4: Systems of Particles [aka Center of Mass] (pdf or Google doc) and Linear Momentum (pdf or Google doc)
Unit 5: Rotation (pdf or Google doc)
Unit 6: Oscillations (pdf or Google doc)
Unit 7: Gravitation (pdf or Google doc)