The Catalog of Sims astronomy Solar System basics cosmology gravitation historical orbits stars math functions numbers trigonometry vectors physics Rotations and Torque circular-motion coordinates electrostatics forces historical kinematics light modern momentum optics oscillations rotation sound waves astronomy Simulations orbits Binary Systems Play with 2 gravitationally interacting masses View The Sim! About/Instructions Effective Potential and Gravity Change to orbital parameters to modify the effective potential as a function of r. View The Sim! About/Instructions Kepler's Second Law Equal Areas in Equal times View The Sim! About/Instructions historical The Celestial Sphere A 3d model of the ancient celestial sphere concept. View The Sim! About/Instructions Epicycles Simulator A tool to visualize epicycles View The Sim! About/Instructions Solar System Doug's Solar System Adjust the parameters of a custom solar system View The Sim! About/Instructions The Earth in Orbit (simplified) A 3d model earth in orbit around the sun View The Sim! About/Instructions A (long) Day on Mercury A simulation that shows the length of a day on Mercury View The Sim! About/Instructions cosmology Expanding Universe An expanding universe has no center. View The Sim! About/Instructions gravitation A simple gravity assist Watch a smaller body getting a gravity assist from a larger body View The Sim! About/Instructions Tidal Forces Observe the effects of tidal forces on a two body system View The Sim! About/Instructions Two Body Orbits - One large One large and one small body in orbit View The Sim! About/Instructions Two Body Orbits Two bodies orbiting a common barycenter View The Sim! About/Instructions stars Stellar Parallax Interactive diagram show how stellar parallax arises. View The Sim! About/Instructions Star Color and Temperature Observe the relation between temperature and color of star View The Sim! About/Instructions Star Color and Temperature Observe the relation between temperature and color of star View The Sim! About/Instructions basics Retrograde Motion See how apparent retrograde motion is created in a heliocentric solar system. View The Sim! About/Instructions Solar day vs. Sidereal day A solar day is just a little longer than a sidereal day. See how! View The Sim! About/Instructions math Simulations functions The Line Tangent to a Function See the tangent line at various points along a curve View The Sim! About/Instructions The Origins of Sine and Cosine Functions Rotations around the unit circle can make sinusoidal functions. View The Sim! About/Instructions Adjustable Parabola Plot Change the coefficients that determine a parabola View The Sim! About/Instructions Adjustable Sine Function Change the coefficients that determine a basic sine function View The Sim! About/Instructions A Damped Sinusoidal Function Change the coefficients that determine a basic sine function View The Sim! About/Instructions Square Wave Fourier Series Summing up certain sine waves will produce a square wave View The Sim! About/Instructions Beating shown graphically Add two sine waves and change the relative frequency of one, slightly View The Sim! About/Instructions Sum of Two Sine Waves Add two sine waves and change the relative phase View The Sim! About/Instructions Triangle Wave Fourier Series Summing up certain sine waves will produce a triangle wave View The Sim! About/Instructions trigonometry Hyperbolic Angles See the relation between normal angles for a circle and their hyperbolic analogues. View The Sim! About/Instructions numbers Orders of Magnitude How big is a circle that is 100 times wider? View The Sim! About/Instructions Visualizing Averages The average of any two quantities can be seen graphically View The Sim! About/Instructions vectors Random Walk A Random walk or two or twenty View The Sim! About/Instructions Vector Addition View The Sim! About/Instructions Vector Components View The Sim! About/Instructions physics Simulations kinematics Ball Slides down a Ramp A simple motion diagram for a ball sliding down a ramp View The Sim! About/Instructions Ball Drop - Free Fall and Measure Drop a ball, and measure its height View The Sim! About/Instructions Ball Drop - Horizontal Velocity Drop a ball, and throw one - what happens? View The Sim! About/Instructions Ball Slides Up and then Down a Ramp A simple motion diagram for a ball given an initial velocity up the ramp. View The Sim! About/Instructions A kinematic cart simulator See the ball fall back into the cup. View The Sim! About/Instructions Launch a Projectile A typical projectile motion, with vectors for display. View The Sim! About/Instructions Plot the Kinematics of an Elevator See three graphs of position, velocity, and acceleration for an elevator moving up and down. View The Sim! About/Instructions Inertial Reference Frame Example Which observer has the right view of the bouncing ball? View The Sim! About/Instructions modern The Bohr / de Broglie Model Change the energy level of the electron in this Bohr Model View The Sim! About/Instructions Interactive Galilean Coordinate Transform Adjust the speed of the moving frame. View The Sim! About/Instructions Interactive Minkowski Diagram Adjust the speed of the moving frame and make events. View The Sim! About/Instructions Quantum Scattering Change the parameters affecting quantum scattering. View The Sim! About/Instructions Summing up Many Sine Waves This is an abstract representation of the Uncertainty Principle. View The Sim! About/Instructions momentum Cats in a raft Tossing cats from a raft has never been this fun! View The Sim! About/Instructions rotation Centripetal Acceleration Vectors Observe the acc. and vel. vectors for an object moving in a circle. View The Sim! About/Instructions A box attached to a Massive Pulley Adjust the parameters of a pulley/mass system to see the change in rotation speed and linear acceleration of the falling mass. View The Sim! About/Instructions Rotating Reference Frame Compare the motions of a projectile between reference frames View The Sim! About/Instructions A rotating wheel See the tangential velocity vectors on a rotating wheel. View The Sim! About/Instructions optics Simple Color Mixing Arrange the three circles to experiment with mixing 3 colors View The Sim! About/Instructions Ray Diagram Change the parameters for a converging lens system View The Sim! About/Instructions electrostatics Electric Dipole in an Electric Field Adjust the field strength and observe the effects on the dipole View The Sim! About/Instructions light Double Slit Intensity graph Adjust the variables in a double slit experimental setup to see their effects on the intensity plot. View The Sim! About/Instructions Diffraction Grating Intensity graph Adjust the variables in a n-slit (i.e. diffraction grating) experimental setup to see their effects on the intensity plot. View The Sim! About/Instructions Single Slit Intensity graph Adjust the variables in a single slit experimental setup to see their effects on the intensity plot. View The Sim! About/Instructions Snell's Law See how refraction changes the direction of a light ray View The Sim! About/Instructions historical Force and Motion A replica of an old simulation. View The Sim! About/Instructions Huygens Principle An animated update to a classic figure. View The Sim! About/Instructions forces A Block on a Ramp, with Friction See how a block on a ramp will respond to the angle of the ramp and a shoving force. View The Sim! About/Instructions Mass on a Ramp Free Body Diagram Adjust the angle of a ramp and see how the free body diagram changes. (Does not include friction) View The Sim! About/Instructions oscillations Pendulum Vectors Inspect the acceleration and velocity vectors for a pendulum View The Sim! About/Instructions Pendulum with plots See how a pendulum correlates with the kinematic variables View The Sim! About/Instructions A Spring and its parameters Adjust the parameters of a spring mass system and see the effects View The Sim! About/Instructions coordinates Polar and Cartesian Coordinates An object in circular motion shown in both cartesian and polar coordinates. View The Sim! About/Instructions circular-motion Simple Solar System add planets to a simple solar system View The Sim! About/Instructions sound Radially Propagating Sound Waves soundwaves are oscillations in pressure as function of position and time. View The Sim! About/Instructions Standing Sound Waves in a Closed-Closed Tube soundwaves are oscillations in pressure as function of position and time. View The Sim! About/Instructions Standing Sound Waves in a Closed-Open Tube soundwaves are oscillations in pressure as function of position and time. View The Sim! About/Instructions Standing Sound Waves in an Open-Open Tube soundwaves are oscillations in pressure as function of position and time. View The Sim! About/Instructions Soundwaves soundwaves are oscillations in pressure as function of position and time. View The Sim! About/Instructions Two Speakers - 1D interference The spacing between two speakers changes the interference of the sound waves. View The Sim! About/Instructions waves A Standing Wave with Labels A standing wave labeled with node and antinode and adjustable wavelength. View The Sim! About/Instructions A Standing Wave A standing wave formed by two traveling waves and adjustable angular frequency. View The Sim! About/Instructions Adjustable Traveling Wave Change the coefficients that determine a traveling sine wave View The Sim! About/Instructions Traveling Wave Amplitude Note how the amplitude affects a transverse traveling wave View The Sim! About/Instructions Traveling Wave Vectors Visualize the velocity of the constituent particles of a traveling wave. View The Sim! About/Instructions Traveling Wave A simple traveling wave showing the motion of the medium. View The Sim! About/Instructions Wave in a medium See the wavelength change as a wave passing thought different mediums View The Sim! About/Instructions Rotations and Torque Torque on a Wrench Adjust the position, angle, and magnitude of a force applied on a wrench. View The Sim! About/Instructions