Double Rayleigh Model

The Ejs Two Orbiting Masses with Relative Motion model displays the dynamics of two masses orbiting each other subject to Newtonian gravity. The simulation displays the motion of the masses in the inertial reference frame and the relative motion as seen from one of the masses. The initial energy...

The EJS Molecular Dynamics Demonstration model is constructed using the Lennard-Jones potential truncated at a distance of 3 molecular diameters. The motion of the molecules is governed by Newton's laws, approximated using the Verlet algorithm with the indicated Time step. For sufficiently small...

The Circular Well model displays the 2D energy eigenstates of a particle trapped in a very deep two-dimensional circular well. Because the Schr?*A*dinger equation for this system is separable into radial and angular differential equations, the solution can be expressed as a product of a Bessel...


Platforms: Mac

The Noon Shadow model shows the geometry of the shadow cast by a gnomon at noon. Users can change the orientation of the gnomon as well as its latitude. The height of the gnomon and its shadow length are displayed in Earth radius units. It is a supplemental simulation for an article by Barbara...


Platforms: Mac

The Ejs Non-Newtonian Orbit model displays the dynamics of a mass orbiting a much larger mass subject to non-Newtonian gravity. The simulation displays the motion of the smaller mass and the effective potential energy diagram. The initial energy of the system can be changed via textbox and the...


Platforms: Mac

The Ejs Duffing Chaos 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 two solutions with different initial positions and a plot of phase. The evolution...


Platforms: Mac

The Ejs Orbiting Mass with Spring Force model displays the frictionless dynamics of a mass constrained to orbit on a table due to a spring. The simulation displays the motion of the mass as well as the effective potential energy. The initial velocity, k/m, and the proper or natural length of the...


Platforms: Mac

The Ejs Spherical Pendulum model displays the dynamics of a spherical pendulum in three dimensions. The pendulum is initially displaced from equilibrium and the pendulum bob has zero initial velocity. You can modify this simulation if you have Ejs installed by right-clicking within the plot and...


Platforms: Mac

The Ejs Spinning Hoop model displays the model of a bead moving along a hoop which is spinning about its vertical diameter with constant angular velocity ?. Friction is negligible. The simulation displays the motion of the bead as well as a plot of angle vs. time for the bead. The angular...


Platforms: Mac

The Ejs Anisotropic Oscillator model displays the dynamics of a mass connected to two opposing springs. The simulation displays the motion of the mass as well as the trajectory plot. The initial position of the mass can be changed by dragging. The unstretched lengths of the springs can changed as...


Platforms: Mac

The Ejs Duffing Poincare 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 Poincare plot. The evolution parameters can be changed via textboxes....


Platforms: Mac

The Ejs Standing Waves in a Pipe model displays the displacement and pressure waves for a standing wave in a pipe. The pipe can be closed on both ends, on one end, or open on both ends. The number of nodes in the standing waves can be changed via a slider. You can modify this simulation if you...


Platforms: Mac

The Ejs Two Source Interference model displays the interference pattern on a screen due to two point sources. The simulation allows an arbitrarily superposition of the two sources and shows both the current intensity and running average of the intensity on the screen. The separation, phase...


Platforms: Mac

The Spring Motion Model shows the motion of a block attached to an ideal spring. The block can oscillate back-and-forth horizontally. You can change the mass of the block, the spring constant of the spring, and the initial position of the block. You can then see the resulting motion of the block,...


Platforms: Mac

The Thin Film Interference model investigates reflection and transmission of light through a thin film. The user can change the thickness and index of refraction of the thin film as well as the incident light wavelength. The Thin Film Interference Model was created using the Easy Java...


Platforms: Mac

The EJS Ballistics and Orbits model displays ballistic trajectories near the Earth. The model shows the trajectory with respect to the inertial coordinate system and the trajectory as seen from a point of view that is co-rotating with the Earth. You can examine and modify this simulation if you...


Platforms: Mac

The Ejs Standing Waves on a String model displays the motion of a standing wave on a string. The standing wave can be augmented by adding the zero line and the maximum displacement of the string. The number of standing waves shown can be changed via a slider. You can modify this simulation if you...


Platforms: Mac

The Ejs Pendulum on an Accelerating Train model displays the model of a pendulum on an accelerating train. The problem assumes that the pendulum rod is rigid and massless and of length, L = 2, and the pendulum bob is of mass, m = 1. The initial pendulum angle and the initial velocity of the train...


Platforms: Mac

The Scalar Field Gradient Model displays the gradient of a scalar field using a numerical approximation to the partial derivatives. This simple teaching model also shows how to display and model scalar and vector fields using EJS. The EJS Scalar Field Gradient Model was created using the Easy...


Platforms: Mac

The Point Charge Electric Field Demo model shows the electric field with multiple point charge configurations and vector field visualizations. Users can select these configurations from a drop down menu or can create their own configurations. The Point Charge Electric Field Demo model was...


Platforms: Mac