Readytorun

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...

The Momentum Space package is a self-contained file for the teaching of the time evolution and visualization of energy eigenstates and their superpositions via momentum space in quantum mechanics. The file contains ready-to-run OSP programs and a set of curricular materials. The material focuses...

The STP Entropy Einstein Solid program calculates the entropy of two Einstein solids that can exchange energy. The purpose of this calculation is to illustrate that the entropy is a maximum at thermal equilibrium. The default system is two Einstein solids with 50 particles each and total energy E...


Platforms: Mac

The Ejs Platform on Two Rotating Cylinders model displays the model of a platform resting on two equal cylinders are rotating with opposite angular velocities. There is kinetic friction between each cylinder and the platform. The separation between the cylinders and the coefficient of kinetic...


Platforms: Mac

The STP IdealQuantumGas program is a simulation of an ideal quantum gas in equilibrium with a heat bath. The program computes the density of states, particle distribution function, and energy occupancy diagram. The default system is a three-dimensional ideal Fermi gas of N=100 particles at...


Platforms: Mac

The STP IdealFermiGasIntegral program numerically determines the value of the chemical potential of an ideal Fermi gas for a given temperature and density. STP IdealFermiGasIntegral is part of a suite of Open Source Physics programs that model aspects of Statistical and Thermal Physics (STP)....


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

The Spherical Mirror Model demonstrates the focusing of light using a spherical mirror. The user can change the size and position of the object, the focal length of the mirror and the rays shown in the diagram. The Spherical Mirror Model was created using the Easy Java Simulations (EJS) modeling...


Platforms: Mac

The Refraction of Light Package explores light traveling through media of difference indices of refraction. The user can change the beginning and end points of the light ray as well as the location of the light at the interface and note what light path minimizes light travel time and thereby...


Platforms: Mac

The EJS Faraday Disk Dynamo shows a conducting disk that rotates in a magnetic field. This produces a current (homopolar generator) and for certain configurations, it is a self-exciting dynamo. A self-exciting dynamo is the mechanical analog of a proposed mechanism to produce the earth and sun's...


Platforms: Mac

The EJS Ceiling Bounce Model shows a ball launched by a spring-gun in a building with a very high ceiling and a graph of the ball's position or velocity as a function of time. Students are asked set the ball's inital velocity so that it barely touches the ceiling. This simple model is a designed...


Platforms: Mac

The STP ChemicalDemon program displays a histogram of the energy of a demon that exchanges energy and particles with a one-dimensional lattice of particles. The purpose of this simulation is to understand how the demon acts as an ideal thermometer and ideal measurement of the chemical potential....


Platforms: Mac

The Point Charge Forces in Two-Dimensions model investigates the electric force that a charged particle experiences in a two-dimensional situation, because of four other nearby charged particles. The net electric force is shown as an arrow attached to the particle. Note that each particle can be...


Platforms: Mac

The Ejs Damped Driven Simple Harmonic Oscillator model displays the dynamics of a ball attached to an ideal spring with a damping force and a sinusoidal driving force. The spring is initially unstretched and the ball has zero initial velocity. The initial position of the ball can be changed by...


Platforms: Mac

The EJS Falling Loop Model shows a conducting loop falling out of a region of uniform magnetic field. It plots the velocity of the loop as a function of time. Users can change the size and orientation of the loop as well as the extent and location of the uniform field. If Ejs is installed,...


Platforms: Mac

The EJS Ideal Gas Expansion model simulates a two-dimensional ideal gas in a square box. This simulation can be used as part of the activity described in "The Statistical Interpretation of Entropy: An Activity" by Todd Timberlake, to be published in The Physics Teacher. In the model, the...


Platforms: Mac

The Ejs Newtonian Scattering model displays the gravitational scattering of a multiple masses incident on a target mass. The simulation displays the motion of the smaller. The number of particles and their initial spread, the gravitational constant, and the target mass's radius can be changed via...


Platforms: Mac

The Ejs Coin Rolling with and without Sliding model displays the dynamics of an initially rotating, but not translating, coin subject to friction. The simulation displays the motion of the coin as well as the velocity vectors for the surface of the coin. The initial angular velocity and the...


Platforms: Mac

The QM Probability 2D program displays the time evolution of the two-dimensional probability density using color to represent its magnitude. The default wave function is a two-state superposition in the x (nx = 1,2) and y dimension (ny = 3,4) state in an infinite square well. Additional states...


Platforms: Mac