Tag Archives: physics

AP Annual Conference: Making Sense of Electric Potential

Making Sense of Electric Potential

Jim Vander Weide, Hudsonville High School, MI

I attended this session since electric force, field, potential, and energy are concepts with which students struggle. I have attempted to make connections between these concepts and the corresponding gravitational concepts. I’m interested to see this teacher’s approach.

  • Jim provided slides building an extended analogy between gravitational fields and electric fields as well as other handouts. He would probably be willing to share, and his contact info can be found with a bit of Google-fu :)

AP Annual Conference: Results from AP Physics Exams

Results from AP Exams

Jiang Yu, Chief Reader

I attended this session to gain some insights into how the AP Physics B exam is scored and what common mistakes students made on the exam.

  • Question B1
    • 6.6/10
    • common errors
      • omit one of the three forces or add a normal force on FBD
      • use unconventional labels for their forces
      • units! students often omitted units
      • not recognize buoyancy is measured in Newtons
      • forces that appeared on the FBD often did not match the ones appeared in subsequent calculations
      • not using physics but general language in justification
  • Question B2
    • 6.0/15
    • common errors
      • applied kinematic equations for constantly accelerated motion to a motion of changing acceleration
      • not recognize that W=Fd can only be used when F is constant
      • not knowing that spring force is not a constant force
      • explanations are not concise and clear
  • Question B3
    • 3.6/10
    • common errors
      • non-linear scaling of axes in graphing
      • best-fit line often is drawn by just connecting points
      • not showing work for calculating slope of the best-fit line
      • not understanding that the light must pass from a higher index of refraction to a lower index of refraction in order to have total internal reflection
  • Question B4
    • 3.6/10
    • common errors
      • not reading the question carefully and not answering what is asked
      • not showing enough work beginning with the correct equations and then all the needed steps leading to an answer
      • messing up the horizontal and the vertical dimensions in calculations
      • deficiency in understanding the conservation of momentum
      • using “energy,” “force,” “momentum” and “velocity” interchangeable in explanations
  • Question B5
    • 3.6/10
    • common errors
      • misunderstanding of the sign conventions in evolved for heat, work and energy
      • not clear with their justifications, but often simply restated the question, and answer without providing further support
      • connected heat or average kinetic energy to temperature, but not to the internal energy
      • used W = -PΔV and did not discuss the effect of temperature on the pressure
  • Question 6
    • 3.5/15
    • common errors
      • simple calculations errors were everywhere
      • incorrect use or value of the magnetic permeability, μo, in Ampere’s Law
      • not understanding the intent of parts (a) & (b)
      • did not clearly understand the nature of the question and the connection of the parts to each other
  • Question 7
    • 2.7/10
    • common errors
      • the most common errors were the result of a lack of understanding of atomic states and associated energy levels. Students seemed to choose and use the equations without basic understanding of the physics involved.

AP Annual Conference: AP Physics 1 and 2 Courses

AP Physics 1 and 2 Courses

Connie Wells, Co-Chair, Physics 2 Development Committee

Karen Lionberger, College Board’s AP Program Director, Science Curriculum and Content

I attended this session to learn as much as possible about the new AP Physics 1 and 2 courses as we are “piloting” AP Physics 1 in the context of our Honors Physics course this upcoming school year.

  • Out of 1 million high school freshen interested in STEM majors and careers, 57.4% loose interest and switch to a different career path.
  • Big Ideas -> Enduring Understandings -> Essential Knowledge + Science Practices -> Learning Objectives
  • Physics 1 designed to have a couple of weeks of extra time to cover additional topics to meet requirements for state exams or teacher preference.
  • Big Idea 7 is only addressed in Physics 2. Some new material related to probability.
  • Rigor (or Vigor) = Complexity (and Autonomy) + Engagement
  • Teaching Strategies for Success in the AP Physics 1 and 2 Courses
    • assessment of prior knowledge, beliefs, and misconceptions that students bring with them to the course(s)
    • analysis of how to deal with students’ misconceptions
    • greater depth of conceptual understanding through the use of student-centered, inquiry-based instructional practices
    • use of formative assessments to guide instructional practices and provide feedback to students about depth of understanding
    • planning lessons based on the clearly articulated AP Physics learning objectives
    • integration of student inquiry laboratory work into the course
  • How the Learning Objectives Will Be Assessed
    • ability to solve problems mathematically – including symbolically – but with less emphasis on only mathematical routines used for solutions
    • questions relating to lab experience and analytical skills: designing and describing experiments; data and error analysis
    • questions asking for explanations, reasoning, or justification of answers
    • more emphasis on deeper understanding of foundational principles and concepts
    • interpreting and developing conceptual models
  • laboratory emphasis on students – inquiry-based, hands-on, integrated, investigative and collaborative
  • lab questions will focus more on error analysis and what the next step in the investigation would be
  • students will have to write at least one paragraph-length argument (make a claim and support with evidence) in the short-answer questions
  • 2014 professional development will launch new One-Day and AP Summer Institute Workshops to support the new courses
  • June 2014 – practice exams for both AP Physics 1 and Physics 2
  • sample syllabi available before March 2014
  • course and exam description (including equation sheets) available March 2014
  • course planning and pacing guides (8 total, 4 for each course)
  • teacher’s guide on inquiry-based investigations
  • 2 pacing guides will be available August 1st
  • Advances in AP site
  • 140 instruction hours is the target for AP courses (Physics 1 is targeted at 115-120 to allow time for additional topics)

AP Annual Conference: Learning with Exploring Computer Science

Learning with Exploring Computer Science (ECS): Connections to AP CS

I attended this session to get an overview of Exploring Computer Science and AP Computer Science Principles, determine how these courses may apply to my school’s computer science sequence, and learn how these efforts are able to increase enrollment of underrepresented groups.

Exploring Computer Science (ECS)

  • exploringcs.org
  • Goal: increase student enrollment, especially with females and underrepresented minorities.
  • ECS is a year-long course that includes six curricular units and daily lesson plans. Grew out of the book Stuck in the Shallow End. Funded by the NSF.
  • ECS computer science concepts
    • human-computer interaction
    • problem solving
    • web design
    • introduction to programming
    • computing and data analysis
    • robotics
  • ECS computational practices
    • analyze effects of computing
    • design creative solutions and artifacts
    • apply abstractions and models
    • analyze computational work and work of others
    • communication computational thought processes
    • collaborate with peers on computing activities
  • In the Los Angeles School District, ~2000 students are enrolled in ECS per year; 45% are girls; underrepresented minority enrollment mirrors (or exceeds) enrollment in the district.
  • ECS is also in Chicago Public Schools as well; data forthcoming.

AP Computer Science Principles

Jody Paul

  • involved in APCS, AP Computer Science Principles, and ECS
  • The context within which we teach Computer Science …
    • extreme variation in prior exposure and experience of students
    • misconception: computer science equals writing programs
    • cognitive shifts are associated with acquiring new thinking skills
      • require the passage of time (as well as mentored exercise) to acquire and internalize
      • limited set of skills successful in other domains not sufficient
      • frustration, confusion, bewilderment
  • Success in Computer Science is associated with being adept at:
    • discovery learning & inquiry-based learning
    • understanding when and how to seek assistance from peers, mentors, and references
    • working collaboratively
    • applying creative practices
    • appreciating larger context within which computation exists
    • accepting and working well with the juxtaposition of vagueness and precision
      • problems must be precisely specified
      • there are many correct ways to solve a problem
      • solutions must be creatively developed
      • a solution must be precisely and unambiguously specified
  • Three programs jointly facilitate success
    • leveling influences to accommodate diverse backgrounds
    • establishing meaningful context
    • correcting misconceptions and inappropriate stereotypes
    • initiating mental development processes that facilitate the cognitive shifts necessary for successful study in CS
    • preparing students for progressively increasing rigor and challenge in CS study
    • acquisition of key skills: inquiry, collaboration, algorithmic thinking, …

Q&A

  • AP CS Principles is intended for all 21st Century Students. It is a computer science course; not a programming course.
  • Only 10 states count computer science as a math or science course. Some states have no certification for computer science.
  • ECS, AP CS Principles, and AP Computer Science A are not intended to be a course sequence. All three courses are potential entry points into computer science. The panel seemed to concur that the audience for AP Computer Science A is quite different, and smaller, than the audience for the other two courses. There was a bit of confusion about how ECS and AP Computer Science Principles differ. With my limited exposure, they seem very similar in principle. I wouldn’t envision a high school offering both. The fact that one is AP and one is not may lead a high school toward one over the other. In addition, since ECS is an entire course package (e.g., includes daily lesson plans) while AP CS Principles is a curriculum framework, may lead a high school towards one over the other. I don’t see either replacing our current Programming 1/2 courses, but I could see offering one or the other as an additional course targeted at a much wider audience.

Sharing Resources with Students via Evernote

I love reading about the latest developments in physics and technology. When I began teaching, I started collecting bookmarks for articles that I found online that were related to various topics we would study in class. I also started collecting bookmarks to resources for myself. At the start of each unit, I created a page organizing all of these links to articles, simulations, videos, and projects for students. This page serves as an extension to the class. Many of the topics go beyond the curriculum and are fascinating extensions to the unit of study. I would encourage students to browse this page when they were procrastinating: “If you are procrastinating instead of doing your homework, you might as well browse physics articles.”

I tried to optimize this process as much as possible. I stored the bookmarks in Yojimbo and somewhat automated the process of creating the page for each unit. However, there was still too much effort to keep each unit’s page current. I also wanted to share each unit’s page with a wider audience. Finally, while I collected a large number of links to resources for teachers, I didn’t have a completely automatic way to share them with anyone else.

Based on recommendations from several people, one of my projects this summer was to investigate Evernote. I was pleasantly surprised at how efficient a workflow I could develop.

My first step was to enumerate a superset of units and create an Evernote notebook for each unit. Actually, I created two Evernote notebooks for each unit: one for students and one for teachers:

Evernote Notebooks

I imported my existing bookmarks into Evernote which took a while but doesn’t need to be repeated. Evernote makes it easy to share a notebook publicly. However, I wanted to present the links within a notebook in an organized fashion. So, I created an index for each notebook of student links. This was really easy to do by filtering the notes in the notebook by various tags (articles, simulations, videos, make):

Filtering by Tags

I then selected all of the notes with the specified tag, right-clicked, and copied links to these notes:

Copying Links to Notes

Finally, I pasted these links into the index note under the appropriate heading:

Index Note

I didn’t bother with this level or organization for the notebooks containing teacher-centric links.

I was very pleased to see that it would be easy to keep track of new links that haven’t been added to the index note. Since the notes are sorted by when they are updated, when I start each unit, it is easy to see which links I need to add to the index because they are sorted before the index note:

Newer Notes

When I start each unit next year, I’ll update the index note and post a link to the shared notebook under the current module on Canvas. In addition, I now hope that a wider audience will benefit from these extensions of typical physics units. Evernote has a good web interface for exploring these shared notebooks:

Evernote Web Interface

Shared notebooks for the superset of units across my classes are enumerated on my web site. Feel free to share them with your student and I hope you leverage Evernote to share your own collection of links with your students and other teachers!

AP Physics B Assessments

As I’ve mentioned, I’m spending some time this summer preparing for the AP Physics B course that we will be teaching for the first time this fall. I recently finished creating the assessments for this course.

With one exception (fluids multiple choice), all questions are from previous AP Physics B exams. Thanks to the handy indexes available from Secure PGP, it was relatively easy to review relevant questions and problems and choose those I wanted.

While compiling the assessments, I refined the granularity of the units a bit.

Fall Semester

  • Special Relativity
  • Kinematics
  • Statics and Dynamics
  • Fluid Mechanics
  • Work, Energy, Power
  • Thermodynamics
  • Linear Momentum
  • Oscillations, Gravity, Waves
  • Capstone Project

Spring Semester

  • Electrostatics
  • Electric Circuits
  • Magnetic Fields and Electromagnetism
  • Geometric Optics
  • Physical Optics
  • Particle Physics
  • Atomic Physics and Quantum Effects
  • Nuclear Physics
  • Cosmology

For each unit, I compiled a quiz that contains representative free response problems to be used as a formative assessment. I then created an end-of-unit exam consisting of multiple choice and free response questions. The exam is intended to be completed in a 50-minute class period or less. To support the flavor of standards-based grading that I’m using in this class, I also created a reassessment consisting of multiple choice and free response questions. Scoring rubrics for all free response questions have also been compiled for each assessment.

I uploaded the assessments as an archive for each semester to Secure PGP. I included the original Pages documents as well as versions exported as PDFs and Word files. I hope that some of you find these helpful. Please let me know if you find any mistakes.

Reflection and Refraction Activities

We are currently in the midst of the geometric optics unit in my honors physics class and just finished waves, which includes reflection and refraction, in my regular physics class.

My colleagues and I have developed a series of reflection and refraction activities that provide a shared experience that can be leveraged as we explore reflection and refraction of light. In addition, students find these activities engaging and they generate a lot of great questions.

I hope you find a new activity that you can use in class.

Here are the handouts.

Reflection of Light

Refraction Activities

I don’t have photos of the reflection activities, but I think they are pretty self explanatory. If not, ask, and I’ll clarify.

I do have photos of the refraction activities. I need to give credit for the first activity which is a recreation of an AAPT Photo Content winner from a few years ago.

Colored paper behind glasses

Colored Paper behind Water Glasses

Pencil in air oil water

Pencil in Air, Oil, and Water

Toy car in beaker 1

Toy Car in Round Beaker

Masses Hiding in Fish Tank (Total Internal Reflection)