Model Train Track
The Lagrangian Pendulum Spring model asks students to solve the Lagrangian for a spring-pendulum and then develop a model of it. It is distributed as a ready-to-run (compiled) Java archive. Double-clicking the ejs_CM_Lagrangian_pendulum_spring.jar file will run the program if Java is installed....
Platforms: Mac
License: Freeware | Size: 1.3 MB | Download (34): CM Lagrangian Pendulum Spring Model Download |
The Fourier sine series model displays the sine series expansion coefficients of an arbitrary function on the interval
Platforms: Mac
License: Freeware | Size: 1.4 MB | Download (38): Fourier Sine Series Model Download |
The STP XY Model program implements a Monte Carlo simulation of the planar ferromagnet or XY Model of spins on a lattice. The simulation returns the configuration of spins with the option of showing the vortices. The default system is a lattice of linear dimension L = 20 at temperature T = 0.89....
Platforms: Mac
License: Freeware | Size: 489.47 KB | Download (41): XY Model Download |
The Kicked Rotor model shows the dynamics of a rotating bar (rotor) that is kicked periodically. This model is also known as the standard map or the Chirikov-Taylor map. Each impulsive kick changes the angular momentum of the rotor instantaneously and the bar rotates uniformly between kicks....
Platforms: Mac
License: Freeware | Size: 737.28 KB | Download (36): Kicked Rotor Dynamics Model Download |
The Newton's Law of Cooling model computes the temperature of an object of mass M as it is heated by a flame and cooled by the surrounding medium. The model assumes that the temperature T within the object is uniform. This lumped system approximation is valid if the rate of thermal energy...
Platforms: Mac
License: Freeware | Size: 1.2 MB | Download (36): Newton's Law of Cooling Model Download |
The Ejs Harmonics and Fourier Series model displays the sum of harmonics via a Fourier series to yield a new wave. The amplitude of each harmonic as well as the phase of that harmonic can be changed via sliders. In addition, several pre-set functions can be chosen to display. You can modify this...
Platforms: Mac
License: Freeware | Size: 1.34 MB | Download (38): Harmonics and Fourier Series Model Download |
The Falling Slinky model approximates a slinky using twenty masses connected with light springs. The slinky is suspended from one end and released. Two actions will occur simultaneously when it is released hanging at rest from its equilibrium position - it will fall and it will collapse. What...
Platforms: Mac
License: Freeware | Size: 102.4 KB | Download (36): Falling Slinky Model Download |
The EJS Binomial Distribution Model calculates the binomial distribution. You can change the number of trials and probability. 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 Binomial...
Platforms: Mac
License: Freeware | Size: 81.92 KB | Download (37): Binomial Distribution Model Download |
The Ejs Coupled Oscillators and Normal Modes model displays the motion of coupled oscillators, two masses connected by three springs. The initial position of the two masses, the spring constant of the three springs, the damping coefficient for each mass, and the driving force and driving force...
Platforms: Mac
License: Freeware | Size: 1.35 MB | Download (45): Coupled Oscillators and Normal Modes Model Download |
The Kepler System model simulates Kepler's final theory of planetary motion. In this theory the planets orbit in ellipses with Sun at one focus (Kepler's First law). These elliptical orbits are not necessarily all in the same plane. A line from Sun to the planet sweeps out equal areas in equal...
Platforms: Mac
License: Freeware | Size: 1.35 MB | Download (37): Kepler System Model Download |
The Ejs Celestial Globe model simulates the Two Sphere Universe theory of the Ancient Greeks. This theory supposes the stars to be fixed on the surface of a Celestial Sphere, with the spherical Earth at the center of this sphere. The simulation shows the motion of Sun and stars in this model, as...
Platforms: Mac
License: Freeware | Size: 1.29 MB | Download (35): Celestial Globe Model Download |
The Ejs N-body Orbits model displays the dynamics of three to five identical masses orbiting each other subject to Newtonian gravity. The simulation displays the periodic orbital motion of the masses. The initial configuration of the system can be changed via slider. You can modify this...
Platforms: Mac
License: Freeware | Size: 1.34 MB | Download (37): N-body Orbits Model Download |
The Ejs Doppler Effect model displays the detection of sound waves from a moving source and the change in frequency of the detected wave via the Doppler effect. In addition to the wave fronts from the source a graph depicting the time of emission and time of detection of each of the wave fronts...
Platforms: Mac
License: Freeware | Size: 1.41 MB | Download (35): Doppler Effect Model Download |
The Ejs Circumnavigating Pendulum model displays the dynamics of a mechanical oscillator in uniform circular motion. The mechanical oscillator is free to move in two directions. This 2-dimensional simulation displays all the dynamical features of the Foucault pendulum, except for the dependency...
Platforms: Mac
License: Freeware | Size: 10.24 KB | Download (43): Circumnavigating Pendulum Model Download |
The Rocking Semicircular Hoop model shows the dynamics of a simple object rocking without slipping on a horizontal surface. It is a supplemental simulation for an article by Leaf Turner and Ari Turner "Asymmetric rolling bodies and the phantom torque" in the Am. J. Phys. 78, 905 (2010). The...
Platforms: Mac
License: Freeware | Size: 785.41 KB | Download (37): Rocking Semicircular Hoop Model Download |
The Ejs Orbiting Mass on a Table 3D model displays the frictionless dynamics of two masses that are attached via a string through a hole in a horizontal table. Mass m moves on the table in two dimensions while mass M hangs vertically and just moves up and down. The simulation allows displaying...
Platforms: Mac
License: Freeware | Size: 1.67 MB | Download (40): Orbiting Mass on a Table 3D Model Download |
The Ejs Driven Diatomic Oscillator Chain model displays a one-dimensional diatomic chain of coupled harmonic oscillators with one end driven by an external force and the other end attached to a sliding rod shock absorber. The mass and Stoke's Law damping for the shock absorber are chosen to...
Platforms: Mac
License: Freeware | Size: 1.18 MB | Download (37): Driven Diatomic Oscillator Chain Model Download |
The Heating and Cooling a Cylinder model computes the radial temperature distribution within a long cylinder as it is heated and cooled by a surrounding fluid. The cylinder is broken into shells and the temperature of each shell is computed using a finite difference approximation to the radial...
Platforms: Mac
License: Freeware | Size: 10.24 KB | Download (40): Heating and Cooling a Cylinder Model Download |
The EJS Magnetic Bar Field Model shows the field of a bar magnet and has a movable compass that reports the magnetic field values. The bar magnet model is built by placing a group of magnetic dipoles along the bar magnet. You can modify this simulation if you have Ejs installed by right-clicking...
Platforms: Mac
License: Freeware | Size: 92.16 KB | Download (40): Magnetic Bar Field Model Download |
The Ejs Duffing Oscillator model computes the solutions to the non-linear Duffing equation, which reads, x'' + 2?zN*x' - x (1 - x2) = f cos(?Ya*t), where each prime denotes a time derivative. The simulation displays the solution as well as the phase space and Poincare plots, and energy diagram....
Platforms: Mac
License: Freeware | Size: 1.37 MB | Download (39): Duffing Oscillator Model Download |