New Open Source Physics collection resources

Improving students’ understanding of quantum measurement. II. Development of research-based learning tools

Wed, 16 May 2012 19:49:03 EST

We describe the development and implementation of research-based learning tools such as the Quantum Interactive Learning Tutorials and peer-instruction tools to reduce students’ common difficulties with issues related to measurement in quantum mechanics. A preliminary evaluation shows that these learning tools are effective in improving students' understanding of concepts related to quantum measurement.

Analytic Trajectory Animator Model

Mon, 14 May 2012 21:36:50 EST

The Analytic Animator allows instructors to create two-dimensional single-particle kinematics models for teaching. Instructors set two functions, x(t) and y(t), and the model displays the position-space particle motion as well as position, velocity, and acceleration graphs and tables. The customized simulation is then saved with associated curricular as a new jar file that can be redistributed. The Analytic Trajectory Animator Model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_newton_TabletopProjectile.jar file will run the program if Java is installed.

Dynamic Trajectory Animator Model

Fri, 11 May 2012 11:23:16 EST

The Dynamic Trajectory Animator allows instructors to create two-dimensional single-particle Newtonian dynamics models for teaching. Instructors set two functions, Fx(t) and Fy(t), and the model displays the position-space particle motion as well as position, velocity, and acceleration graphs and tables. The customized simulation is then saved with associated curricular as a new jar file that can be redistributed. The Dynamic Trajectory Animator Model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_newton_TabletopProjectile.jar file will run the program if Java is installed.

Tilt Maze Game Model

Tue, 08 May 2012 20:13:57 EST

The Tilt Maze Game Model is set on a plane that can be tilted to make the ball roll due to gravity. The plane can be tilted up, down, to the left and to the right. By tilting the planes, the user must cause the ball to move through the maze to get to the hole at the top left side of the maze...but be careful, there are some traps laid out that would stop you from accomplishing your goal. The Tilt Maze Game Model was developed using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the jar file will run the program if Java is installed. You can modify this simulation if you have EJS installed by right-clicking within the map and selecting "Open Ejs Model" from the pop-up menu item.

Improving Students' Understanding of Quantum Mechanics

Fri, 04 May 2012 08:14:52 EST

This thesis uses a number of Open Source Physics simulations to explore issues related to students’ common difficulties in learning upper-level undergraduate quantum mechanics and how these difficulties can be reduced by research-based learning tutorials and peer instruction tools. The thesis investigated students’ difficulties in learning quantum mechanics by administering written tests and surveys to many classes and conducting individual interviews with a subset of students. Based on these investigations, the thesis developed Quantum Interactive Learning Tutorials (QuILTs) and peer instruction tools to help students build a hierarchical knowledge structure of quantum mechanics through a guided approach. Preliminary assessments indicate that students’ understanding of quantum mechanics is improved after using the research-based learning tools in the junior-senior level quantum mechanics courses. The thesis author also includes a standardized conceptual survey that can help instructors better probe students’ understanding of quantum mechanics concepts in one spatial dimension. The validity and reliability of this quantum mechanics survey is discussed.

Tracker Video Analysis: Wall of Death

Wed, 02 May 2012 05:43:37 EST

Can a vehicle can ride around the inside vertical wall of a cylinder? The video analysis in this item explore the physics behind the Wall of Death. The zip file contains the Wall of Death blog entry, a video of a car riding the wall, and a Tracker video analysis file. A discussion of the physics for a car on the wall was posted on the Dot Physics blog for Wired. A second blog entry describes the physics of a motorcycle on the wall.. To open the Tracker file, download and run Tracker from http://www.cabrillo.edu/~dbrown/tracker/. Tracker is free.

One-dimensional collision carts computer model and its design ideas for productive experiential learning

Wed, 02 May 2012 05:40:47 EST

We develop an Easy Java Simulation (EJS) model for students to experience the physics of idealized one-dimensional collision carts. The physics model is described and simulated by both continuous dynamics and discrete transition during collision. In designing the simulations, we discuss briefly three pedagogical considerations namely (1) a consistent simulation world view with a pen and paper representation, (2) a data table, scientific graphs and symbolic mathematical representations for ease of data collection and multiple representational visualizations and (3) a game for simple concept testing that can further support learning. We also suggest using a physical world setup augmented by simulation by highlighting three advantages of real collision carts equipment such as a tacit 3D experience, random errors in measurement and the conceptual significance of conservation of momentum applied to just before and after collision. General feedback from the students has been relatively positive, and we hope teachers will find the simulation useful in their own classes.

Tracker Video Analysis: Remote Control Helicopter

Mon, 30 Apr 2012 07:48:45 EST

How much can a remote control helicopter lift? The video analysis in this item explores the physics behind a toy helicopter. The zip file contains the Dot Physics blog entry, a video of the flying helicopter, and a Tracker video analysis file. A discussion of helicopter physics was posted on the Dot Physics blog for Wired. To open the Tracker file, download and run Tracker from http://www.cabrillo.edu/~dbrown/tracker/. Tracker is free.

Tracker Video Analysis: Angry Birds in Space

Tue, 24 Apr 2012 13:37:13 EST

What type of force is exerted on Angry Birds in Space? The video analysis in this item explore the physics behind the game. The zip file contains the Angry Birds Space blog entry, a video, and the Tracker file. To open the Tracker file, download and run Tracker from http://www.cabrillo.edu/~dbrown/tracker/. Tracker is free. The Angry Birds video came from Rovio, the makers of Angry Birds Space: http://www.youtube.com/watch?v=9-hjAY0XpvE. Dot Physics is a physics blog for Wired.

Pinhole Camera Model

Fri, 20 Apr 2012 11:16:05 EST

The Pinhole Camera Model demonstrates the operation of a pinhole camera. Light rays leaving the top and bottom on an object of height h, pass through a pinhole, and strike a flat screen. These rays travel in straight lines in accord with the principles of geometric optics. Drag the object and observe the image on the camera screen. Simple geometry shows that the image is inverted and that the ratio of the image to object size (the magnification) is the same as the ratio of the image to object distance. The Pinhole Camera Model was developed using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the jar file will run the program if Java is installed. You can modify this simulation if you have EJS installed by right-clicking within the map and selecting "Open Ejs Model" from the pop-up menu item.

Building a National Digital Library for Computational Physics Education Podcast

Sun, 15 Apr 2012 14:40:55 EST

A Davidson College Center for Teaching and Learning podcast that describes the interactive pedagogy that motivated the development of the ComPADRE Open Source Physics Collection. Current efforts to improve computational physics education in the United States are presented.

Flat Mirror Model

Thu, 12 Apr 2012 19:54:23 EST

The Flat Mirror Model shows two principal rays leaving a candle of height h and striking a flat mirror. The first ray is parallel to the mirror surface and is reflected back on itself. The second ray strikes the mirror a distance h below the flame. The angle between the reflected ray and the surface normal is the same as that between the incident ray and the normal in accord with the principles of geometric optics. If the reflected rays are extended behind the mirror, the location of the virtual image is observed. The Flat Mirror Model was developed using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the jar file will run the program if Java is installed. You can modify this simulation if you have EJS installed by right-clicking within the map and selecting "Open Ejs Model" from the pop-up menu item.

Learning and Teaching Mathematics using Simulations – Plus 2000 Examples from Physics

Mon, 09 Apr 2012 08:14:44 EST

This work takes an experimental approach to understanding mathematics through the use of interactive Java simulations. Suggestions for experiments to perform are included for over 60 interactive EJS models created by the author and a collection of over 2000 java simulations in physics. Topics covered include infinitesimal calculus, partial differential equations, fractals and much more. Intervention and customization of the calculation programs is possible using the EJS (Easy Java Simulation) simulation technology. A module library also allows users to engage in further development. In the electronic version of the text, the examples can be accessed directly from the text and operated online or from an installed package. The interactive format is an ideal tool to help users visualize and understand mathematics and physics and their simulation techniques.

Geostationary Earth Orbit Satellite Model

Sun, 08 Apr 2012 15:13:20 EST

The Geostationary Earth Orbit Satellite Model is a simple angular velocity model that uses Java3D for a realistic visualization of satellites in geostationary orbits. Students can view and explore the behavior of geostationary orbits, non-geostationary orbits, and non-physical orbits. This model tests the Java 3D implementation of the EJS 3D library. A warning message will appear if the Java 3D library is not available. The Geostationary Earth Orbit Satellite Model was developed using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the jar file will run the program if Java is installed. You can modify this simulation if you have EJS installed by right-clicking within the map and selecting "Open Ejs Model" from the pop-up menu item.

Continuous Cellular Automata Model

Tue, 03 Apr 2012 14:28:19 EST

The Continuous Cellular Automata Model creates a one-dimensional array of rational numbers Xi and applies a rule that determines how each cell evolves from one generation to the next. The numerators and denominators of numbers Xi are stored as arbitrary precision Big Integer objects so all computations are exact. Because arbitrary precision arithmetic is computationally intensive, we use the Parallel Java library to implement the model. The Continuous Cellular Automata Model was developed by Wolfgang Christian using the Easy Java Simulations (Ejs) modeling tool. It is based on the One-Dimensional Continuous Cellular Automata model in Chapter 17 of the book "Building Parallel Programs" by Alan Kaminsky.

Stick Falling from Table Model

Tue, 28 Feb 2012 09:06:58 EST

The Stick Falling from Table Model shows the translational and rotational motion of a stick falling from a table. The normal and gravitational force vectors and the center of mass trajectory are shown. Users can vary the initial velocity of the stick and height of the table. The stick's motion occurs in three phases. In first phase, the stick slides along the tabletop without rotating until the CM reaches the tabletop edge. In the second phase, the gravitational force acts at the CM and a normal force acts at the edge to produce both linear and angular accelerations. In the final phase, the stick is no longer in contact with the table and free-falls with constant angular velocity and constant CM acceleration. The model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_newton_StickFallingFromTable.jar file will run the program if Java is installed.

One Dimensional Wave Function Superposition Model

Sun, 26 Feb 2012 11:26:26 EST

The One Dimensional Wave Function Superposition Demonstration Model shows how the superposition principle gives rise to wave phenomena such as standing waves and beats. Users enter real-valued wave functions and observe both the time dependent functions and their superposition. You can modify this simulation if you have Ejs installed by right-clicking within the plot and selecting “Open Ejs Model” from the pop-up menu item. The One Dimensional Wave Function Superposition Demonstration Mode was developed using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the model's jar file will run the simulation if Java is installed.

Driven Pendulum with Phase Space Model

Wed, 22 Feb 2012 18:30:51 EST

The Driven Pendulum with Phase Space Model computes and displays the dynamics of a damped and driven pendulum, its phase space, and its Poincare section. The model displays pendulum motion in the main window and the phase space in a second window. Because a phase space trajectory can be very complicated, the motion is easier to analyze by plotting a point in phase space after every cycle (period T) of the external force. Such a phase space plot is called a Poincare map. The Driven Pendulum with Phase Space Model was developed using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the model's jar file will run the simulation if Java is installed.

Breaking AES Encryption Model

Sat, 18 Feb 2012 18:32:50 EST

The Breaking the AES Cipher Model encrypts a plaintext message using AES encryption and attempts to break this encryption using a plaintext attack. The attacker (Eve) obtains both the plaintext and the cyphered text for a message between two people, Alice and Bob, and systematically encrypts the plaintext using the AES encryption function with all possible keys until the function's output matches the known cyphered text. Eve starts with a key, feeds the key and the plaintext into the encryption function, and checks whether the cyphered text is equal to the known value. If so, Eve has found the correct key. Otherwise, Eve systematically changes the key until she is successful. If the key is small or if Eve knows some of the key, the computational task may be manageable. This model displays the computation time using both a sequential and a parallel do-loop implementation of the plaintext attack. The model is designed to show how Java performs standard AES encryption and to test the speedup and sizeup of parallel computation using multi-core processors. The Breaking the AES Cipher Model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the model's jar file will run the simulation if Java is installed.

Sand Pile Avalanche Model

Sun, 12 Feb 2012 15:20:22 EST

The Sand Pile Avalanche Model simulates the occurences of avalanches in sand piles and plots the frequencies of the size of these avalanches. The general shape, size, and growth of a sand pile is easy to model as new sand grains are added. Although the pile assumes a conical shape, a new grain of sand can trigger an avalanche which causes some number of grains to slide down the side of the cone into new positions. These avalanches are chaotic and it is nearly impossible to predict if the next grain of sand will cause an avalanche, where that avalanche will occur on the pile, how many grains of sand will be involved in the event, and so on. The avalanche models have been related to other more chaotic phenomena, such as the frequency and intensity of earthquakes, historical fluctuations in cotton prices, extinction of species, sizes of cities, and solar eruptions.