Oscillations and Waves


Mechanical Oscillations and Wave Simulations

Pendulum
A simple, large visible pendulum.

Pendulum with Variable Plane of Oscillation
Period of a pendulum can be increased by tilting its plane of oscillation.

Coupled Pendulum
Two pendula connected by a soft spring.

Wilberforce Pendulum
Demonstrates coupling between longitudinal and torsional oscillations of a spring with a hanging mass.

Mass on Spring
Demonstrates simple harmonic motion and can be damped with water.

Bowed String
Oscilloscope shows velocity and displacement graphs of bowed violin string.

Chladni Figures
A functional generator powers a mechanical oscillator with a circular or square plate attached to its center. Sprinkle sand on the plate and observe Chladni figures.

Lissajous Figures
Spectacular laser-drawn figures as a result of the combination of two perpendicular sinusoidal oscillations with varying frequencies and phases.

Mirror on a Membrane

Spectacular laser-drawn figures as a result of the combination of two tones propagating a mirror on a silicone membrane.

Harmonograph

Demonstrates the effects of coupled pendulums

Longitudinal Wave Demo
Helps visualize longitudinal waves.

Slinky
Stretched on the instructor’s table and compressed with rapid pulses from one end, slinky helps to demonstrates longitudinal waves.

Rubber Rope
Demonstrates the properties of transverse waves (includes polarization).

Motor-driven Rubber Rope
Used to demonstrate standing waves.

Bell Wave Machine
Parallel rods attached to a wire demonstrate the properties of transverse waves. Can show wave propagation, wavelength vs. velocity and frequency, standing waves, and so on.

Wave Model
Produces images of traveling and standing waves on an overhead projector or document camera.

Interference Model
Concentric circles drawn on two transparent plastic plates can be used to show the interference patterns.

Ripple Tank
Demonstration is built for OHP, but a modified setup is available for a video camera. Waves are created by one or two point sources or by a straight rod. Interference and diffraction patterns can be observed.

Elliptical Reflecting Chamber for OHP
Shows constructive interference, similar to “whisper chambers” and can be used for “quantum mirage” explanation in quantum mechanics.

Rope Waves
Shows the difference in wave speed between ropes of different types


Resonance

Movie – Collapse of Tacoma Narrows Bridge
This movie shows the collapse of a bridge due to resonant oscillations induced by a mild breeze.

Hacksaw Blade Oscillator
Demonstrates forced and damped harmonic oscillations at resonant frequency.

Resonating Metal Strips
Strips with different length are attached to the oscillator that’s driven by a functional generator. Demonstrate the relationship between length, frequency, and resonance.


Sound Waves

Sound Interference
A “double slit” interference pattern can be set up using a frequency generator connected to 2 speakers. Nodal lines can be spaced so that students can move their heads back and forth and hear a big amplitude difference.

Beats
Two versions are available: with 2 tuning forks or with 2 frequency generators connected to 2 speakers.

Resonating Tube
A tall plastic column with a speaker mounted on the top. Can be used with or without water. Produces loud resonances as water level changes. Helps to understand how wind musical instruments work and calculate speed of sound.

Tuning Forks
A set of musical tuning forks and forks with resonators are available. Can be used to produce harmonic sounds, beats, and other effects.

Xylophone
Made for educational purposes. Has twelve metal plates to produces notes.

Rijke’s Pipe
Vertical, open-ended tube with a piece of metal gauze inside. The gauze is heated with a bunsen burner. Creates a loud sound while cooling.

Bell in a Vacuum
An electric bell is placed inside a bell jar. Bell is audible until vacuum pump creates vacuum.

Rubens Tube
The flaming oscilliscope

Simple and Complex Sounds
Visual display of sound waves associated with tuning forks and human voices.

Fourier Synthesizer
A Fourier synthesizer generates combinations of harmonics at variable amplitudes and phases. Superposition of these harmonics can create square, triangle or saw-tooth waves.

Harmonic Analysis of Musical Notes
Example of the harmonic content of the sound produced by different musical instruments.

Doppler Effect Demonstration
Siren on string swinging overhead. Audience hears different pitch when siren is approaching or receding.