The Bell Jar Summary

The QM Position Measurement program displays the time evolution of the position-space wave function and can be used to simulate the quantum-mechanical measurement of position. The default wave function is an equal-mix four-state superposition in the infinite square well. QM Position Measurement... Platforms: Mac

The Optics Interference program simulates a ripple tank by showing the intensity of waves produced by a point source. Adding multiple point sources creates easily observable interference patterns showing constructive and destructive interference. Users can add point sources, move them around, and... Platforms: Mac

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

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

The Gaussian Wave Packet: Step Scattering model simulates the time evolution of a free Gaussian wave packet in position space when it is incident on a potential energy step. The position-space wave functions are depicted using three colors on the graph: black which depicts the absolute square of... Platforms: Mac

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

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

The 3-D Hydrogen Atom Probability Densitites model simulates the probability density of the first few (n = 1, 2, and 3, and associated l and m values) energy eigenstates for the Hydrogen atom (the Coulomb potential). The main window shows the energy level diagram for the solutions to the Coulomb... Platforms: Mac

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

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

The EJS Radioactive Decay Model simulates the decay of a radioactive sample using discrete random events. It displays the number of radioactive nuclei as a function of time. You can change the initial number of nuclei and the decay constant as well as changing the plot to a semi-log plot. The... Platforms: Mac

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

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

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

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

The Ejs Phase Space Plotter model displays the dynamics of an ensemble of pendula or simple harmonic oscillators in phase space (velocity versus position). Friction is initially set to zero but can be changed via a textbox as can the number of elements in the ensemble. For the pendulum ensemble,... Platforms: Mac

The Fermat Light Ray model shows a light ray traveling left to right through N homogeneous regions with different refractive indicies. Because light travels in a straight line through a homogenous medium, the path is determined by the vertical coordinates at each boundary. A data table allows... Platforms: Mac

The QM Wigner program displays the time evolution of the position-space wave function and the associated quasi-probability distribution in phase space via the Wigner function. The default wave function is a Gaussian wave packet in a harmonic oscillator. Additional states and other potential... Platforms: Mac

The GR Kerr Light program simulates the path of light in the equatorial plane near a rotating black hole using the Kerr metric. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the gr_kerr_light.jar file will run the program if Java is installed. The default setting is... Platforms: Mac

The STP LJ2DMetropolis program is a Monte Carlo simulation of Lennard-Jones particles in two dimensions in contact with a heat bath. The default initial condition is a rectangular configuration of N=64 particles in a box of length L = 18 and a temperature T= 1. STP LJ2DMetropolis is part of a... Platforms: Mac