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Oscillations and Waves

  1. Simple Harmonic (and non-harmonic) Motion
    • SHM Demonstrator Relation between circular motion and linear displacement on OHP. (s) (T) ***
    • Circular Motion and SHM Simultaneous shadow projection of circular motion and bouncing weight on spring. (l) (T+) **
    • Masses on Springs. Numerous combinations of springs and masses to bounce. (s/m) (T)
    • 1.47 Slug Oscillator Large mass on spring; traces displacement/time on passing acetate sheet. (l) (T++) ***
    • Skyhook Pendulum. The combination of a 70 Newton ball suspended by a 100 N spring scale is used to investigate forces in one and two dimensional motion of the pendulum. (m)(T+)
    • Physical Pendulum A rigid rod executes SHM about an adjustable pivot point. (m) (T) **
    • Reversible (Kater's) Pendulum A physical pendulum with two adjustable knife edges for an accurate determination of "g". (m) (T) **
    • Non-uniform Physical Pendulum Half wood and half metal physical pendulum with suspension points at both ends. (m) (T) *
    • Cycloidal Pendulum. A pendulum is made to swing on a cycloidal path thereby making it isochronous, regardless of amplitude. (m) (T+)
    • Torsional Pendulum. Oscillation of mass on wire in torsional mode. (m) (T+)
    • Torsional Cube Pendulum. A torsional pendulum with a cubic mass; by suspending the cube along various symmetry axes, the moment(s) of inertia can be verified. (m) (T)
    • Damped Mass-Spring Oscillator. Vertical mass-spring oscillator which can be driven at various frequencies with and without damping. (m) (T+)
    • Driven Oscillator. Single air track glider, with and without variable frequency driver, variable damping, and oscilloscope position vs. time display. (l) (T+)
    • Air Track Oscillator. Glider with reflector makes use of sonar Mac that measures displacement, velocity, and acceleration of simple harmonic motion. (l) (T++)
    • Mass with Two Vertical Springs. Normal modes of vibration of a single mass with three degrees of freedom. (m) (T)
    • Tuning Forks Selection of mounted tuning forks and rubber hammer. (m) (T) **
    • x3 oscillator. An oscillator whose restoring force is not proportional its the displacement; air-track and air-table versions for 1 and 2-dimensions. (l) (T++)
  2. Coupled Oscillations and Resonance
    • Coupled Oscillators. Long pendulums coupled by spring; also a pair of hacksaw blades magnetically coupled. (m/s) (T)
    • OHP Coupled Oscillators. Magnetically coupled oscillators which can be driven to show two normal modes of vibration; one oscillator can also be tuned. (s) (T+)
    • Three Coupled Oscillators. Three hacksaw blade oscillators electromagnetically driven to demonstrate three normal modes of vibration. (s/m) (T+)
    • Air Track Coupled Oscillators. Two or more gliders, coupled by springs, driven to show normal modes of vibration. (l) (T+)
    • Non-linear Oscillations. Air track glider/oscillator with a spring arrangement so that restoring force is proportional to (displacement)2. (l) (T++)
    • Chaotic Pendulum Coupled, double, physical pendulum executes chaotic motion when non-linear initial conditions are imposed. (m) (T) ***
    • 'Y' Suspended Pendulum. Pendulum with two distinct periods...superposition of normal modes of oscillation. (m) (T)
    • Sand Pendulum. Pendulum leaks sand onto black paper leaving a record of rotating ellipsoidal motion. (l) (T+)
    • Ellipsometer. Physical pendulum with analog x and y displacement readout on storage oscilloscope. (m) (T+)
    • Shattering Wineglass Large speaker with signal generator/amplifier destroys a wineglass; stroboscopic illumination shows vibration mode. (l) (T++) ****
    • Barton's Pendulum Ten coupled pendulums of different lengths; shows resonance and phase. (l) (T) ****
    • Chladni Plates Two-dimensional vibrating solids, excited into modes by bow. (s) (T+) ****
    • Big Chladni Plate Electromagnetically driven plate to show modes of vibration. (l) (T+) ***
    • Frahm Resonance Gyroscope Vibrational resonances of metal reeds are excited by a spinning gyro as it slows down. (s) (T) **
    • Parametric Excitation. A pendulum is set into motion by periodically pulling on the string at the proper frequency. (m) (T+)
    • Inverted Pendulum A physical pendulum finds stability in its inverted position when driven at the proper frequency and amplitude combination. (s) (T+) ***
    • Rotating Saddle Mechanical analog of a Paul Trap particle confinement - a ball is trapped in a time-varying quadrupole gravitational potential. (l) (T) ****
    • Dust Particle Paul Trap. An electrically charged dust particle is trapped in a time-varying (60 Hz) quadrupole electric field. (s) (T+)
  3. Travelling Waves
    • Shive Wave Machine Rods attached to metal spine; transverse wave generator shows the reflection of waves free, fixed, terminated and transition boundaries. (m) (T) ****
    • Slinkys, Springs and Rope. Generate your own transverse and longitudinal waves; pulse reflections from free and fixed ends are possible. (m/l) (T)
    • Slinky Wave Cradle Longitudinal wave demo with suspended slinky. (l) (T) ***
    • Ripple Tank. Generation of wavefronts from selection of sources. (l) (T++)
    • Russian Wave Machine. Hand cranked transverse wave model. (m) (T)
    • Wave in a Tank. A two-fluid model shows the slow propagation of shallow water waves. (m) (T)
    • Group/Phase Velocity. The group velocity of two harmonic waves can be shown (on an oscilloscope) to be less than or greater than the individual phase velocities. (m) (T+)
  4. Standing Waves
    • Wave Speed. The speed of sound in an aluminum rod is determined by measuring its frequency and the length of the rod. (l) (T+)
    • Shive Wave Machine Torsional standing waves can be set up. (m) (T) ****
    • Driven Rope or Wire. The fundamental as well as many harmonics are seen and heard on a wire driven at various frequencies. (l) (T+)
    • Standing wave on Long Spring Obtain as many harmonics as your arm can handle. (m) (T) ***
    • Longitudinal Standing Waves. A vertically supported slinky is hand-driven to secure longitudinal standing waves. (m) (T+)
    • Standing Wave in Metal Rod An aluminum rod, supported in the middle, rings for a long time in its longitudinal mode. (m) (T) ***
    • Standing Wave On Soap Film. Normal modes of vibration on a soap film are acoustically excited. (m) (T++)
    • Resonant Fountain Tube Standing sound waves in a glass pipe are made evident by the fountains of kerosene inside the pipe. (l) (T+) ****
    • Standing Waves in a Tube. A glass tube is tuned to set up a standing wave for the particular excitation frequency. (m) (T+)
    • Whirl-a-tune. A corrugated plastic tube sings as it is swung about. (m) (T)
    • Bunsen Burner Glass Tubes. White noise from hot turbulent air turns glass tubes into awesome organ pipes. (m) (T+)
    • Chladni Plates Two-dimensional vibrating solids; accumulation of sand at nodes on plate reveals mode of vibration. (s) (T+) ****
    • Big Chladni Plate Large vibrating plate with sand accumulation at nodes revealing mode of vibration. (l) (T+) ***
    • Ripple Tank. By selection of wave generation with signal generator, standing waves can be set up. (l) (T++)
    • Ring of Fire Gas flames in a ring, height of flame determined by standing wave within torus. (m) (T+) ****
  5. Sound
    • Velocity of Sound. Velocity of sound is determined by measurement of frequency and length of standing wave. (m) (T+)
    • Inverse Square Intensity Fire bell and decibel meter. (m) (T+)
    • No Sound Through a Vacuum. A bell, ringing in a bell jar, ceases to be heard as the bell jar is evacuated. (l) (T+)
    • Sound Waves in a Room. Three dimensional standing waves are generated in the lecture hall and detected by students moving about. (l) (T+)
    • Doppler Ball Plastic Wiffle Ball with built-in shriek to throw past (or at) your audience. (s) (T) ***
    • Doppler Turntable Two speakers, one at each end of rotating platform; beating due to frequency shift of speakers travelling in opposite directions. (l) (T+) **
    • Doppler Whirler A high-pitched alarm on the end of a rope is whirled about the head. (m) (T) ***
    • Doppler Tuning Forks Run towards the blackboard carrying a tuning fork... (m) (T) **
    • Refraction of Sound. Balloons filled with helium and CO2 act as diverging and converging lenses, respectively. (m) (T+)
    • Helium and Sulphur Hexaflouride Change pitch of organ pipes by changing sound velocity. (m) (T) **
  6. Music
    • Tuning Forks Selection of mounted tuning forks and rubber hammer. (m) (T) **
    • Tuning Fork and Baffle. Sounding a tuning fork with and without a baffle demonstrates its purpose and effectiveness. (s) (T)
    • Organ Pipes. Selection of single organ pipes, open and close-ended, to blow through. (m) (T)
    • Monochord. Frequency vs string length and tension are explored on this single string instrument (m) (T)
    • Harmonics. Harmonics are generated on the monochord with the application of appropriate boundary conditions. (m) (T)
    • Siren Discs. Spinning disks, perforated with holes, "sing" when air is blown through the holes. (m) (T)
    • Musical Bottle. A beer bottle becomes a Helmholtz resonator when air is blown across its mouth. (s/m) (T)
    • Variable Whistles. Variable frequency Galton whistle. (s) (T)
    • Fourier Synthesizer. Nine harmonics can be used to generated wave forms seen on a oscilloscope. (l) (T+)
    • Fourier Analyzer. Frequency power spectrum of sounds is measured and displayed. (l) (T+)
    • White/Pink Noise Generator. A special machine to make...noise. (m) (T+)
  7. Interference and Diffraction
    • Sound Cancellation. The sound from two speakers destructively interferes. (m) (T+)
    • Beats Two tuning forks with similar frequencies; one fork is variable in frequency to tune beating. (s) (T+) ***
    • Mechanical Beating. Shadow projection of the superposition of two circular motions exhibits beating phenomenon. (l) (T+)
    • Double-source Interference. Stationary spatial interference pattern from two point sources is displayed on OHP. (s) (T)
    • Comb Interference. Spatial beats between two combs on OHP. (s) (T)
    • Ripple Tank Interference. Interference patterns of water waves generated by different sources. (l) (T+)
    • Diffraction of Sound. Interference of sound waves from two loudspeakers. (l) (T+)
    • Lissajous Figures. Summation of sinusoidal waves on oscilloscope in x-y mode. (m) (T+)