Porter S Five Forces Model

The Eratosthenes model displays the shadows cast by two gnomons (sticks) at different locations on Earth. For one gnomon, Sun is directly overhead (as would be the case if the gnomon was on the Tropic of Cancer at the summer solstice). The other gnomon is due north of the first gnomon. The sizes...

The Ejs Resonance in a Driven String model displays the displacement of taut string with its right end fixed while the left end is driven sinusoidally. The driving frequency, amplitude, and the simulation's dt can be changed via text boxes and the motion can be further fine tuned by zooming in...

The Pendulum Motion Model shows the motion of a simple pendulum. You can change the mass of the pendulum bob, the length of the string, the acceleration due to gravity, and the initial position of the pendulum. You can then see the resulting motion of the pendulum, as well as see bar graphs of...


Platforms: Mac

The Ejs Quartic Potential Orbit model displays the dynamics of a mass orbiting a much larger mass subject to a quartic potential, C/r4. 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...


Platforms: Mac

The Three Point Charges is an inquiry-based model for exploring the force between charged objects. Initially, the simulation sets up three charged objects, one at each corner of an equilateral triangle. The charges have different magnitudes, represented by force vectors. The charges can be moved,...


Platforms: Mac

The Ejs Great Circles model displays the frictionless motion of a particle that is constrained to follow the surface of a perfect sphere. The sphere rotates underneath the particle, but since there is no friction, and the sphere is perfectly spherical, the motion of the particle is not influenced...


Platforms: Mac

The Ejs Copernican System model illustrates Copernicus' system of planetary motions. The entire system is centered on the center of Earth's uniform, circular orbit. Sun is placed near, but not at, this center point. The orbit of each planet (other than Earth) consists of a deferent circle,...


Platforms: Mac

The Magnet Falling Through Ring model shows the dynamics and the induced current when a magnet falls through a conducting ring. The current in the ring is computed by electromagnetic induction using to Faraday's law and the induced emf is proportional to the negative of the rate of change of...


Platforms: Mac

The Local Coordinates model displays the position of a star in local (Altitude/Azimuth) coordinates. The horizon is shown along with the four cardinal directions (N, E, S, and W). The latitude of the observer is set at 35.5 degrees which sets the location of the north celestial pole (teal)...


Platforms: Mac

The Einstein Cannon model computes and displays the trajectory of cannonballs (particles) shot from a cannon in the vicinity of a black hole. It was created for the study of Einstein's theory of general relativity and the Schwarzschild metric. The main window displays a map of space in the...


Platforms: Mac

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...


Platforms: Mac

The Particle Worldline model computes and displays the trajectory of a test particle in the vicinity of a black hole using Schwarzschild coordinates. It was created for the study of Einstein's theory of general relativity and the Schwarzschild metric. The model has input fields displaying the...


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 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 Ejs Orbiting Mass with Constant Force model displays the dynamics of an orbiting mass due to a constant force (a linear potential energy function). The simulation displays the motion of the mass as well as the effective potential energy. The initial conditions can be changed by dragging the...


Platforms: Mac

The Confined Lennard-Jones System is an idealized statistical mechanics model that simulates a two-dimensional system of particles confined to a box with a constant temperature thermal reservoir at one end and a movable piston at the other. Particles in this model have unit mass and interact...


Platforms: Mac

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...


Platforms: Mac

The Model Analyzer Tool is a compact and user-friendly Windows software specifically crafted for analyzing and evaluating modeling results. Tailored features make it a comprehensive solution for model analysis, providing informative insights. The tool's capabilities include the creation of...


Platforms: Windows, Windows 8, Windows 7, Windows Server

Serious fun! Stunning Clock - Silver screen saver. From Aktiva-s CompanyAktiva-S Time Collection Screen Saver Features:Specially designed atmosphereAlmost Photo realistic graphicsUnique sound environmentMany types of clocks and watches with animationsMultiple backgrounds with effectsAdjustable...

Serious fun! Stunning Clock -Calendar screen saver. From Aktiva-s CompanyAktiva-S Time Collection Screen Saver Features:Specially designed atmosphereAlmost Photo realistic graphicsUnique sound environmentMany types of clocks and watches with animationsMultiple backgrounds with effectsAdjustable...