Model Railroad Wiring Dcc
The Ejs Inertial Oscillation model displays the motion of a particle moving over the surface of an oblate spheroid. The spheroid is flattened to an ellipsoid of revolution because it is rotating, just as the Earth is flattened because it is rotating. The particle is confined to motion along the...
Platforms: Mac
License: Freeware | Size: 1.05 MB | Download (36): Inertial Oscillation Model Download |
The EJS Equinox Precession model illustrates the Copernican theory of Earth's orbit around the sun. The top window shows a view from outside the celestial sphere. The simulation shows the moving Earth along with its axis or rotation and the line of sight from Earth, through Sun, to the Celestial...
Platforms: Mac
License: Freeware | Size: 1.32 MB | Download (36): Equinox Precession Model Download |
The Ejs Coin Rolling without Sliding on an Accelerated Platform model displays the dynamics of a coin rolling without slipping on an accelerated platform. The simulation displays the motion of the coin as well as the velocity vectors for the surface of the coin and the platform. The initial...
Platforms: Mac
License: Freeware | Size: 1.33 MB | Download (36): Coin Rolling without Sliding on an Accelerated Platform Model Download |
The Ejs Damped Driven Harmonic Oscillator Phasor model displays the motion of damped driven harmonic oscillator. The resulting differential equation can be extended into the complex plane, and the resulting complex solution is displayed with the real part of this solution being the position of...
Platforms: Mac
License: Freeware | Size: 1.38 MB | Download (36): Damped Driven Harmonic Oscillator Phasor Model Download |
The Ejs Quartic Oscillator model displays the motion of a bead moving without friction along a horizontal rod, while tied to two symmetric springs. Both the motion of the masses and the phase space plot are shown in the simulation. The natural length of the springs can be changed via textboxes....
Platforms: Mac
License: Freeware | Size: 1.34 MB | Download (37): Quartic Oscillator Model Download |
The Ejs Normal Modes on a Loaded String model displays the motion of a light string under tension between two fixed points. The string is also loaded with N masses located at regular intervals. The number of masses on the string can be changed via textboxes. You can modify this simulation if you...
Platforms: Mac
License: Freeware | Size: 1.35 MB | Download (40): Normal Modes on a Loaded String Model Download |
The Ejs Strange Harmonic Oscillator model displays the motion of two masses connected by a massless rigid rod and the masses may move without friction along two perpendicular rails in a horizontal table. The energy of the oscillator system can be changed via a slider. You can modify this...
Platforms: Mac
License: Freeware | Size: 1.43 MB | Download (41): Strange Harmonic Oscillator Model Download |
The Driven Mass and Spring Mesh model displays the dynamics of a 2D array of masses coupled by springs and driven by a sinusoidal force. The model shows a time-dependent animation of the displacement or each mass. The driving force can be applied at a single point (shown in red) or uniformly at...
Platforms: Mac
License: Freeware | Size: 1.06 MB | Download (36): Driven Mass and Spring Mesh Model Download |
The Diffraction and Interference Model: Single and Double Slits shows diffraction and interference patterns from a single slit, double sources and double slits. The user can change the source wavelength, slit width, separation and distance between slit and screen. The Diffraction and...
Platforms: Mac
License: Freeware | Size: 808.96 KB | Download (38): Diffraction and Interference Model: Single and Double Slits Download |
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...
Platforms: Mac
License: Freeware | Size: 860.16 KB | Download (35): Eratosthenes Model Download |
The Ejs Waves and Phasors model displays the motion of a transverse wave on a string and the resulting phasors for the wave amplitude. The simulation allows an arbitrarily polarized wave to be created. The amplitude, period, phase velocity and number of phasors displayed can all be changed via...
Platforms: Mac
License: Freeware | Size: 1.32 MB | Download (37): Waves and Phasors Model Download |
The Ejs Transverse Wave model displays the motion of a transverse wave on a string. The simulation allows an arbitrarily polarized wave to be created. The magnitude of the components of the wave and the relative phase between the components of the wave can all be changed via sliders. You can...
Platforms: Mac
License: Freeware | Size: 1.4 MB | Download (36): Transverse Wave Model Download |
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...
Platforms: Mac
License: Freeware | Size: 1.36 MB | Download (37): Resonance in a Driven String Model Download |
The EJS Angular Acceleration of a Contracting System model shows a mass and pulley system to illustrate what happens when a rotating system contracts. When the centripetal force has contracted a rotating system to half its initial radius then: (1) The tangential velocity has doubled, (2) The...
Platforms: Mac
License: Freeware | Size: 1.08 MB | Download (39): Angular acceleration of a Contracting System Model Download |
The Ejs Spring Pendulum model displays the model of a hollow mass that moves along a rigid rod that is also connected to a spring. The mass, therefore, undergoes a combination of spring and pendulum oscillations. The initial position and velocities, as well as the spring constant can be changed...
Platforms: Mac
License: Freeware | Size: 1.37 MB | Download (36): Spring Pendulum Model Download |
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
License: Freeware | Size: 1.41 MB | Download (35): Pendulum Motion Model Download |
The Orbits Within Spherical Galaxies model displays the two-dimensional trajectories of particles (stars) within a galaxy having a spherically symmetric mass distribution that heuristically approximates the distributions found in galaxies and bulges. The model uses a mass density proposed by...
Platforms: Mac
License: Freeware | Size: 1.4 MB | Download (35): Orbits Within Spherical Galaxies Model Download |
The Ikeda Delay Differential Equation model shows the dynamics of a delay differential equation that depends on the value of the dynamical variable x(t) at a previous time x(t-?). Sprott shows that these systems provide elegant examples of chaos in systems that are too simple to exhibit chaos...
Platforms: Mac
License: Freeware | Size: 778.24 KB | Download (37): Ikeda Delay Differential Equation Model Download |
The Ejs Two Falling Rods model displays the dynamics of two rods which are dropped on a smooth table. In one case the end point on the table slides without friction, while in the other case it rotates about a pivot point. The simulation allows computing fall times and trajectories. The initial...
Platforms: Mac
License: Freeware | Size: 1.4 MB | Download (42): Two Falling Rods Model Download |
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
License: Freeware | Size: 1.35 MB | Download (35): Quartic Potential Orbit Model Download |