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Quantum Physics and Relativity

  1. Quantum Mechanics
    • Black Body Radiation Lamp Tungsten filament lamp whose color is temperature dependant in accordance with Planck's radiation law. (m) (T) *
    • Wien's Displacement Law. Changes in the spectral intensity distribution of a hot tungsten filament are observed as the temperature is varied. (l) (T+)
    • Purcell's Black Body Box Cardboard box black body; interior looks black despite being painted white. (m) (T) ***
    • Black Body Radiation Oven Clay and iron objects within a kiln; all radiate with same color when at thermal equilibrium. (l) (T+) ***
    • Tether-ball Catastrophe Ball on string attached to rod; see the classical electron spiral into the nucleus! (m) (T) **
    • Photoelectric Effect Discharge of electroscope using carbon arc UV source. (l) (T++) ***
    • Planck's Constant Determination Spectral lines from mercury lamp incident on phototube; energy of photons equated to photoelectron stopping potential. (l) (T++) ****
    • Electron Diffraction Cathode rays incident on crystal samples. (m) (T+) ***
    • Uncertainty Principle Energy/time reciprocity relation using electromagnetic waves; simultaneous display in energy (frequency) and time domains. (l) (T++) ***
    • Optical Analog of Uncertainty Principle Adjustable single slit diffraction; spatial localization (by slit) results in momentum spread of photons. (m) (T) **
    • Tunneling Analog (Frustrated Total Internal Reflection) To reflect or not to reflect at the interface of two prisms in intimate contact? Adjust the potential barrier. (m) (T+) **
    • Ring of Fire deBroglie wavelength nl=2pr shown by gas flame in a torus. (m) (T++) ****
    • Big Chladni Plate Electromagnetically driven plate to show two dimensional modes of vibration. (l) (T++) ***
    • Single Photon Interference Wave/particle duality observed in Young's double slit experiment with camera sensitive to individual photons. (l) (T+++) ****
  2. Atomic and Molecular Physics
    • Atomic and Molecular Crystal Models Wooden, plastic, and styrofoam models for show-n-tell. (m) (T)
    • Flame Tests. Salts of various elements give off characteristic colors when burned in a flame; diffraction grating reveals discreet colors. (m) (T++)
    • Electrical Discharges in Air. The electrical characteristics of a column of air are observed as a function of pressure. (m) (T+)
    • Tower of Spectra. Assembly of three gas discharge tubes and white light source for spectral analysis with diffraction gratings. (m) (T)
    • Resonance Radiation/Absorption Heated sodium vapor is transparent when illuminated by white light and opaque when illuminated by light from a sodium lamp. (m) (T+) ***
    • Fraunhoffer Absorption Sodium "D" absorption lines are observed when sodium is burned in the optical path of a white light spectrum. (l) (T+) ***
    • Street Lamps Projected emission spectra from large sodium and mercury lamps using elliptic reflectors. (l) (T+) ***
    • Collisional Broadening Na D-doublet absorption lines broaden into one large absorption band due to increase in pressure/temperature. (l) (T+) ***
    • Fluorescent Minerals. Three mineral samples (sealed in a vacuum flask) glow red, green, and blue when bombarded by electrons. (m) (T)
    • Periodic Potential Balls in a frame simulating the repeating potential wells of a lattice. (m) (T) **
    • Field Emission Electron Microscope. The crystalline structure of a tungsten filament is revealed by electron field emission. (m) (T)
    • Mass Spectrometry. A model in which a magnetic field is used to separate steel ball bearings by mass. (m) (T+)
  3. Nuclear and Elementary Particle Physics
    • Rutherford Scattering Model with Air Table Air table with fixed magnetic puck to represent nucleus scatters "projectile" magnetic pucks. (l) (T+) ***
    • Rutherford Scattering Model with Van de Graaff. Charged Christmas tree balls scatter off of Van de Graaff. (m) (T++)
    • Rutherford Scattering Model with Ping Pong Balls Ping Pong ball projectiles scatter of a sphere and into buckets set at different distances (scattering angles). (l) (T+)
    • Pool Table Scattering. Show off your pool skills to demonstrate collisions in two dimensions. (l) (T++)
    • Potential Well Orbiter Circular wooden well, 1m diameter, with 1/r curvature. (m) (T)
    • Roller Coaster Potential Well One-dimensional model of electron trapped in atomic potential well. (m) (T) *
    • Giant Nuclear Potential Well. Use a hammer to enable a ball to overcome potential barrier. (m) (T)
    • CRT Paddle Wheel. A beam of cathode rays (electrons) impinging on a paddle wheel cause it to spin and travel down the vacuum tube. (s) (T+)
    • Determination of e/m. Charge to mass ratio of electron, using electron beam in magnetic field of Helmholtz coils. (l) (T++)
    • JJ Thomson e/m Tube. Similar to preceding demo but the geometry is similar to Thomson's original experiment. (s) (T++)
    • Maltese Cross CRT Maltese Cross obstacle and fluorescing glass show that electrons travel in straight lines and are affected by magnetic fields. (m) (T) ***
    • Cathode Ray Deflection Small Crookes tube with built-in fluorescent screen shows electron beam deflection by magnetic field. (m) (T) ***
    • TV Image Deflection Image on black and white television is deflected by a magnet, not unlike the Maltese Cross. (l) (T+) **
    • Bremsstrahlung X-rays are given off by the stopping of electrons in the Maltese Cross CRT; a glass plate in front of detector shows they are "soft" x-rays. (m) (T+) ***
    • NMR in Earth's Magnetic Field. Hear the protons sing their FID! NMR frequency is in the audio range for earth's field. Videotape of actual experiment. (l) (T+++)
    • NMR Model. Gyro (with axially mounted magnets) positioned inside Helmholtz coils; field is switched by hand at "Larmor frequency" to flip the spinning gyro. (m) (T+)
    • Reversible Fluid Mixing A mechanical analog of spin echoes in NMR. (m) (T+) ****
  4. Radiation and Radioactive Decay
    • Bremsstrahlung X-rays are given off by the stopping of electrons in the Maltese Cross CRT; a glass plate in front of detector shows they are "soft" x-rays. (m) (T+) ***
    • Green Glass Candy Dish This radioactive uranium glass glows beautifully when illuminated by a UV lamp; use as a prop for Becquerel's discovery. (m) (T+) **
    • a, b, g Sources and Detection Radioactive sources with Geiger counter or spark chamber detection. (s/m) (T+) ***
    • a, b, g Penetration and Shielding Testing the effect of different materials in blocking radiation. (m) (T+) ***
    • g Ray Inverse Square Law Testing of g ray intensity with Geiger counter at varioous distances from g source. (l) (T++) ***
    • b-particle deflection Stream of b-particles pass between poles of magnet. (m) (T++) ***
    • Radioactive Human Body Detection of radioactive potassium; display on spectrum analyzer. (l) (T++) ***
    • Thoron Decay Alpha- emission by thoron discharges gold leaf electroscope. (m) (T+) ****
    • Neutron Activation of Silver Measurement of half lives of silver isotopes produced by thermal neutron irradiation. (l) (T++) ****
    • Cloud Chamber Ionization tracks of alpha particles seen in alcohol vapor. (m) (T++) ***
    • Uranium Block Remains of WWII German Atomic Bomb Project. (s) (T) ****
    • Nuclear Fission Array of mouse traps and ping-pong balls; chain reaction triggered by addition of rogue ping-pong ball. (l) (T++) ****
  5. Relativity
    • Relativity Train Demonstration of time dilation and length contraction gedanken experiment using a train on a track. (xl) (T++) ****
    • Bouncing Photon. A photon (modeled by a bouncing ping-pong ball) is observed from two reference frames and provides the motivation for time dilation. (xl) (T++)
    • Faraday Induction Reference frames: equivalence of moving the magnet and moving the coil is shown. (m) (T) **
    • Gravitational Field Surface 1m diameter rubber sheet acts as curved space for ball bearing masses. (m) (T) *
    • Gravitational Lens Laser and plastic lens model of gravitational bending of light by massive objects. (m) (T+) ***
    • Saddle Shape Model Curved space segment. (m) (T) *
    • Expanding Universe Large weather balloon; inflate for two dimensional analogy of the expanding universe. (l) (T+) ***
    • Spherical Blackboard 1m black sphere to draw pretty non-Euclidean diagrams. (m) (T) ***
    • Relativity Grids. Looking at the principle of simultaneity and inertial frames using two parallel 2·D grids.