Physics Experiments

Chaos
Illustrating the chaotic Bunimovich Stadium.	View
The logistic map, which demonstrates the bifurcations of the population levels preceding the transition to chaos.	View
Looking at the Lorenz Attractor in a chaotic regime, allowing the attractor to be rotated.	View
2 fixed suns and 1 planet. Initial conditions are controllable, and up to 4 different independent planets may be displayed.	View
Classical Mechanics
A simple animation showing the difference between the distance and the displacement.	View
1-dimensional kinematics of a body undergoing constant acceleration. Includes visually integrating the acceleration and velocity graphs, and visually differentiating the position and velocity graphs.	View
A car with a non-zero initial speed has a constant acceleration whose value can be controlled by the user.	View
Two balls falling near the Earth's surface under the influence of gravity. The initial horizontal speed of one of the balls may be varied.	View
Illustrating Galilean relativity using his example of dropping a ball from the top of the mast of a sailboat.	View
Firing a projectile when air resistance is negligible. The initial height and angle may be adjusted.	View
A visualization exploration of the kinematics of projectile motion.	View
An animation of the classic lecture demonstration. The actual demonstration is preferable if possible; then this animation can be given to the students for later review.	View
Two balls roll down two different low-friction tracks near the Earth's surface. The user is invited to predict which ball will reach the end of the track first. This problem is difficult for many beginning Physics students.	View
The "Racing Balls" animation which is accessed via the above line sometimes triggers cognitive dissonance and rejection in beginning students. For some of these, changing the balls to skiers helps to clarify the situation, and that is what this animation does. The "Racing Balls" one should be used with students first.	View
Elastic and inelastic collisions on an air track, with different masses for the target cart.	View
A small animation of Newton's Cradle, sometimes known as Newton's Balls.	View
A simple animation illustrating Hooke's Law.	View
An unusual coordinate system for describing circular motion.	View
A mass is in circular motion in the vertical plane. We show the weight and force exerted by the tension in the string.	View
The weight, force due to tension, and total force exerted on the bob of a pendulum are shown.	View
A simple animation that traces the motion of a point on a rolling disc.	View
The direction of the angular velocity vector given by a right-hand screw rule.	View
A simple animation of the direction of the angular velocity vector.	View
Curling rocks and tori sliding across surfaces.	View
The saying is that cats always land on their feet. This animation explains how they do this.	View
A simple animation of a spinning top which processes.	View
Demonstrating that one component of uniform circular motion is simple harmonic motion.	View
Illustrating and comparing Simple Harmonic Motion for a spring-mass system and for a oscillating hollow cylinder.	View
The damping factor may be controlled with a slider. The maximum available damping factor of 100 corresponds to critical damping.	View
A harmonic oscillator driven by a harmonic force. The frequency and damping factor of the oscillator may be varied.	View
Two simple pendulums connected by a spring. The mass of one of the pendulums may be varied. Within mathematical rounding errors, the resolution on the screen of one pixel, and a frame rate of 12 frames per second the animation is correct, not an approximation.	View
Electricity and Magnetism
A simulation of an experiment to determine the dependence of the electrostatic force on distance.	View
A simple DC circuit has a DC voltage source lighting a light bulb. Also shown is a hydraulic system in which water drives a turbine. The two systems are shown to be similar.	View
A simple animation of how a common light Switch works.	View
Illustrating representing an electric field with field lines.	View
A simple buzzer consisting of a battery, a flexible metal strip, a piece of iron, and some wire.	View
An electric charge is executing simple harmonic motion, and the animation shows the electric field lines around it.	View
A 3 dimensional animation of the "far" fields of an oscillating charge.	View
Circular polarization generated from a linearly polarized electromagnetic wave by a quarter-wave plate.	View
A spinning charged object passes through an inhomogeneous magnetic field. This animation is also used in a discussion of the Stern-Gerlach experiment.	View
A spinning charged object passes through an array of 3 magnets each producing an inhomogeneous magnetic field. This animation is also used in a discussion of the Stern-Gerlach experiment.	View
Micrometer Caliper
A simple animation of using a micrometer to measure the width of a pencil.	View
Provides controls to position the micrometer, and when a button is clicked displays the reading.	View
Miscellaneous
A small animation showing a piston compressing a sample of gas. As the volume of the gas goes down, the density and therefore the pressure goes up.	View
An animation illustrating that the derivative of a sine function is a cosine.	View
Illustrating that the area of a circle is a limit of the sum of the areas of interior triangles as the number of triangles goes to infinity.	View
Illustrating the meaning of the integral sign, including an example.	View
Nuclear
Simulating nuclear scattering experiments by scattering ball bearings off targets. This is based on an experiment in the First Year Physics Laboratory at the University of Toronto.	View
The decay of 500 atoms of the fictional element Balonium. Uses a proper Monte Carlo engine to simulate real decays.	View
A simple illustration of electron-positron production and annihilation.	View
Illustrating the 3 principle modes by which X-rays interact with matter.	View
Optics
Illustrating that when a mirror is rotated by an angle, the reflected ray is rotated by twice that angle.	View
Illustrating reflection and refraction, including total internal reflection.	View
Ray tracing for a thin lens showing the formation of a real image of an object.	View
A simulation of an optical bench with a light source, object, thin lens and an image. The screen that displays the image is moved.	View
Oscilloscope
Shows the effect of changing the time base control on the display of an oscilloscope. There is no input voltage.	View
Shows the effect of changing the time base control on the display when there is an input voltage varying in time.	View
Shows the effect of changing the time base control on the display when there is an input voltage varying in time when the frequency of the voltage is high.	View
Shows the effect of changing the voltage control on the display.	View
Shows the effect of changing the trigger level on the display.	View
Quantum Mechanics
The photon excitation and photon emission of the electron in a Hydrogen atom as described by the Bohr model.	View
Here we visualize a hydrogen atom, which consists of an electron in orbit around a proton. In one view the electron is a particle and in the other view it is a probability distribution. The reality is neither view by itself, but a composite of the two.	View
The famous "Feynman Double Slit Experiment" for electrons. Here we fire one electron at a time from the electron gun, and observe the build-up of electron positions on the screen.	View
Here we illustrate Complementarity using the double slit experiment. We view the path of the electron from the gun to the observing screen as a particle and as a wave.	View
Up to three Stern-Gerlach filters with user-controlled orientations are placed in an electron beam.	View
Based on an analysis by Mermin, this animation explores correlation measurements of entangled pairs.	View
Relativity
A simple analogy involving two swimmers that sets up the Michelson-Morley Experiment.	View
A demonstration that the phenomenon of time dilation from the special theory of relativity necessarily follows from the idea that the speed of light is the same value for all observers.	View
A tutorial that shows how relativistic length contraction must follow from the existence of time dilation.	View
This series of animations demonstrates that the relativistic length contraction is invisible.	View
A tutorial that shows how the relative nature of the simultaneity of two events must follow from the existence of length contraction.	View
There are many ways of approaching this classic "paradox". Here we discuss it as an example of the relativistic Doppler effect.	View
This began as an animation of the Foucault Pendulum, but then I generalized it to illustrate Mach's Principle.	View
A simple animation showing Newton's and Einstein's predictions for the orbit of Mercury.	View
Sound Waves
Illustrating beats between 2 oscillators of nearly identical frequencies.	View
Illustrating the wave fronts of a wave for a moving source. There are a few similar animations on the web: this is my re-invention of that wheel.	View
Illustrating the classical Doppler Effect for sound waves.	View
A small animation of a vibrating tuning fork producing a sound wave.	View
This animation shows air molecules vibrating, with each molecule "driving" its neighbor to the right. It is used to illustrate that when the displacement wave is at a maximum then the density of the molecules, and thus the pressure wave, is at a minimum and vice versa.	View
A very brief introduction to the physics and psychophysics of music, with an emphasis on temperament, the relationship between notes.	View
Vectors
A simple demonstration of adding 2 vectors graphically. Also demonstrates that vector addition is commutative.	View
A simple demonstration of adding 3 vectors graphically. Also demonstrates that vector addition is associative.	View
A simple demonstration that subtracting 2 vectors graphically is the same as adding the first one to the negative of the second one.	View
A simple demonstration that to add 2 vectors numerically, just add the cartesian components.	View
A simple animation of unit vectors and vector addition.	View
A simple demonstration of the relation between the dot product of 2 vectors and the angle between them.	View
The direction of the angular velocity vector given by a right-hand screw rule. Requires Flash 6; file size is 196k. Also linked to from the Classical Mechanics section.	View
The direction of the cross product of 2 vectors is demonstrated. The magnitude shown is correct but not discussed.	View
Waves
Illustrating the sign of the time term for traveling waves moving from left to right or right to left.	View
A wave is reflected from a barrier with a phase reversal. This is the behavior for transverse waves and the displacement aspect of a longitudinal wave.	View
A wave is reflected back and forth between two barriers, setting up a standing wave.	View
The first three standing waves for nodes at both ends. The frequencies of the waves are proportional to one over the wavelength.	View
The first three standing waves for a node at one end and an antinode at the other. The frequencies are proportional to one over the wavelength.	View