Physics Lecture Demonstrations

Demonstrations suggested for the text
Halliday & Resnick Fundamentals of Physics, 9nd ed., by
Jearl Walker

Second Semester
Chapters 21 - 44

Revised Fri Aug 12 10:19:21 2011

Chapter21--Electric Charge

EM-a1a Frictional Electricity An electroscope is charged using charged rods.
EM-a2c Party balloon on wall Rub a balloon against your hair or wool shirt and stick it on the wall.
EM-a2e Paper pickup with charged objects Use a comb, PVC rod, glass rod, or other charged object to pick up pieces of paper
EM-a2a Charged Rods on Pivots A charged rod on a pivot is used to show attraction and repulsion by another charged rod.
EM-a3a Conductors and Insulators Shows that charge can be transferred to an electroscope through conductors but not insulators
EM-a4a Electroscope Charged by Induction Charge an electroscope by induction.
EM-a4b Charged Rods and Aluminum Can A charged rod can be used to pull a soda can by electrostatic induction
EM-a5a Wimshurst Machine Generate sparks with a Wimshurst Machine, and explain its workings.
EM-a5b Van de Graaff Generator Describe the operation of the Van de Graaff and show sparks from the ball to a nearby grounded conductor.
EM-b1m Van de Graaff stick Aluminum floaters are held aloft with the Fun Fly Stick
EM-a2d Large Sphere and Ping Pong Ball A small charged ball is repelled from a large charged sphere. Attraction and induction can also be shown.
EM-a5c Van de Graaff Generator--Sound The engine strains more and more as the charge on the dome increases.
EM-b1c Styrofoam Peanut Blowout Styrofoam peanuts in a box on top of the Van de Graaff fly out.
EM-b1e Tart Pan Blowoff Tart pans stacked on top of the Van de Graaff fly off.
EM-b1f Ball Charge Transfer A conductive ball bounces between electrically charged vertical plates
EM-b1i Franklin's Bells A conductive ball bounces between electrically charged bells

Chapter22--Electric Fields

EM-b1b Hair on End Charge yourself with a Van de Graaff generator
EM-b1d Electric Field Visualizer Tiny fibers in a clear oil align in the direction of strong applied electric fields.
EM-b1k Visualizing Field Lines in a Capacitor Use the Electric Field Visualizer with two parallel conductors to show the field lines for a capacitor including edge effects
EM-b1a Oscilloscope Show that an electron beam passing between charged, parallel plates is deflected using an oscilloscope (view along beam)
EM-b3g Lightning Rod Electrical arcing between two large metal spheres abruptly ceases when the lightning rod is touched to one.
EM-b3f Electric Wind with Van de Graaff A point attached to the Van de Graaff blows a hanging piece of cardboard.
EM-b3e Van de Graaff Pinwheel A pinwheel rotates on top of a van de Graaff generator.
EM-b4a Electron Beam Deflection -- Parallel Plates An electron beam is deflected between parallel, oppositely charged plates (viewing beam from side)
EM-d4a Jacob's Ladder An arc rises between rabbit ear electrodes attached to a high voltage source.
EM-b1g Torque on Electric Dipole A small rod aligns between parallel plates

Chapter23--Gauss' Law

EM-b2a Faraday Bucket Show that charge resides on the outside of a hollow conductor.
EM-b2f Gauss with Electric Field Visualizer Tiny fibers in a clear oil that align in the direction of strong applied electric fields remain randomly oriented inside a charged ring.
EM-b2b Radio in a Cage Surround a radio by a Faraday cage and the signal goes away

Chapter24--Electric Potential

EM-b1n Visualizing Electric Potential A voltmeter is used to probe the electric potential between conductors in a water solution.
EM-b3a Surface charge density - conducting balls A pair of large balls with the same separation as a pair of small balls are charged simultaneously with the Wimhurst.
EM-b3b Electric Potential -- Parallel Plates Show that the electric potential varies linearly with distance between Parallel Plates
EM-b3c Charged Ovoid Use a proof plane and an electroscope to compare charge densities at different points on an egg-shaped conductor.


EM-c3b Bulb and 1 Farad Capacitor A large (1 Farad) capacitor is charged with a battery then discharged through a light bulb.
EM-c1a Parallel Plate Capacitor Vary the spacing of a parallel plate capacitor attached to an electroscope.
EM-c1b Rotary Plate Capacitor The rotary plate capacitor is attached to the electroscope.
EM-f3e Capacitors in Series and Parallel Discharge a 0.1F capacitor through a light bulb, and compare with that for three in series and three in parallel
H-d4b Dust Explosion Corn starch dust blown into a flame catches on fire.
EM-c3a Explosive Capacitor Discharge Discharge a 10kV, 1uF capacitor through a thin wire or thick screwdriver
EM-c2a Parallel Plate Capacitor with Dielectric Insert and remove a dielectric sheet from a charged parallel plate capacitor attached to an electroscope.
EM-c2c Force on a dielectric Mineral oil climbs in the gap between parallel plates
EM-c2b Dissectable Capacitor This curious capacitor is charged, disassembled, passed around, assembled, and discharged with a spark.

Chapter26--Current and Resistance

EM-d1a Wire Resistivity Place 6V across a set of wires of different diameters and measure the currents.
EM-d2a Change of Resistance with Temperature A coil in series with a lamp is immersed in liquid nitrogen making the lamp glow brighter.
EM-d2c Conduction in Glass Heat a glass rod with a flame until its resistance is low enough to sustain conduction.
EM-f1a Resistor I-V characteristics Measure and graph the I-V characteristics for a resistor. The value of the resistance may be varied.
EM-f1b Resistance of a Wire Measure the potential drop along a wire
EM-f1e Hot Dog Cooker Spike a hot dog with two nails and cook it.
EM-f2a Series Circuit with Bulbs Show a series circuit of light bulbs
EM-f2b Parallel Circuit with Bulbs Show a parallel circuit of light bulbs
EM-f2c Series Parallel Combination Two bulbs in series with a power supply, and a third bulb in parallel with one of others.


EM-e4b Internal Resistance of Battery Measure the voltage across a battery as its load decreases
EM-c3d Bulb and 1 Farad Capacitor with Oscilloscope A large (1 Farad) capacitor is charged with a battery then discharged through a light bulb, with output monitored with an oscilloscope.
EM-f3d Bulb, 1 Farad Capacitor, and oscilloscope Oscilloscope display of a 1 Farad capacitor discharging through a light bulb.

Chapter28--Magnetic Fields

EM-h2a Magnets on Pivots One magnet is placed on a pivot. The other is used to attract or repel the first
EM-h2b Ring Magnets on a Pole Two or more ring magnets are placed on a vertical pole
EM-h1j Magnet and Iron Filings Panel - 2D visualization Iron filings in a viscous liquid sandwiched between plastic sheets show the path of magnetic field lines. Suitable to pass around
EM-h1e Magnet and Iron Filings -- 3D A bar magnet surrounded in 3D by a clear acrylic tank filled with a liquid containing iron filings.
EM-h3a e/m tube Deflect the beam in an e/m tube with magnets
EM-h3b Oscilloscope and magnet Deflect the beam in an oscilloscope with magnets
EM-h4c AC and DC Lamps A magnet is brought near two carbon filament bulbs, one DC powered and one AC powered.
EM-h4b Force on Current-carrying wire A loop of wire swings to the side of a U-magnet's gap when connected to a current-limited power supply.
EM-h4d Rail Gun -- External Magnet A wheel and axle accelerate along two electrified rails over strong rare-earth magnets
EM-h5a Galvanometer A magnet exerts a torque on a current-carrying coil.
EM-k4c Direct Current Motor Show and explain a DC motor running on batteries.
EM-k4g World's Simplest Motor A simple DC motor that requires only a battery, a bare wire, a nail, and a magnet.
EM-h2c magnetic dipole in external magnetic field Shows that a magnet is rotated but not displaced by a uniform B field, and displaced, but not rotated, by a grad B field where B itself is zero.

Chapter29--Magnetic Fields due to Currents

EM-h1a Oersted Experiment on Overhead Show that current in a wire deflects a compass needle.
EM-h1k B-Field due to long straight wire Iron filings are sprinkled on a plexiglas plate through which a long vertical current-carrying wire passes.
EM-h1m B-Field due to single coil. Iron filings are sprinkled on a plexiglas plate through which a single loop of current-carrying wire is mounted
EM-h1d Magnet and Compass Array -- 2D A small magnet on top of the magnetic domain model apparatus
EM-h4a Force Between Two Current Carrying Conductors Show on the overhead projector that long parallel wires with currents in the same (opposite) directions attract (repel).
EM-h1n B-Field due to solenoid Iron filings are sprinkled on a plexiglas plate through which a current-carrying solenoid is mounted.

Chapter30--Induction and Inductance

EM-k1a Induction Coil and Magnet A magnet is moved in and out of a coil connected to a galvanometer
EM-k1b Induction with Coils and Battery Attach one coil to a galvanometer, another to a battery and tap switch. Use a core to increase coupling
EM-k2a Eddy Current Pendulum A copper sheet, a comb, a ring, and a broken ring are swung through a large electromagnet.
EM-k2b Magnets and Eddy Tubes Drop magnet and a non-magnetic dummy down an aluminum tube.
EM-k2c Magnet and Copper Tube Drop magnet down a short length of straight copper tubing and watch it fall.
EM-k2g Induction Flashlight This flashlight runs on induction-induced currents, a capacitor, and an LED lightbulb.
EM-k2d Jumping Rings A solid conducting ring sitting on a vertical solenoid jumps and a split ring doesn't
EM-j1b Back EMF with light bulb A light bulb in parallel with an inductor flashes when its power is disconnected.
EM-j1c Inductance Spark -- classroom version A bright spark is produced when an inductor is disconnected from a power supply
EM-j2a Series RL circuit: L/R charge/discharge "Charging" and "Discharging" of inductor shown with square wave and oscilloscope
EM-j2b Series RL circuit: L/R phase shifts Show phase shifts in a series RL circuit using the oscilloscope.

Chapter31--Electromagnetic Oscillations and Alternating Current

EM-J3a non-driven LRC circuit oscillations Show the oscillations (ringing) when a charged capacitor is connected in series to an inductor and small resistor.
EM-k4a AC Generator Rotating a wire loop in a magnetic field generates an AC current in the loop.
EM-k4b DC Generator Generate a DC current by rotating a loop with a split-ring connection in a magnetic field.
EM-k4d Hand-held DC Generator Use the handheld generator to illuminate a bulb.
EM-L2a 60 Hz LRC circuit Shows the potential difference across the Capacitor and Inductor at resonance.
EM-L2b LRC circuit with function generator Show the relative phases and amplitudes for the potential differences across the components of an driven LRC circuit.
EM-L2d RC Circuit -- Phase relations Show the potential difference across the power supply, the resistor, and the capacitor as a function of frequency, resistance, or capacitance.
EM-L2e RL Circuit -- Phase relations Show the potential difference across the power supply, the resistor, and the inductor as a function of frequency, resistance, or inductance.
EM-L2f driven LRC circuit at resonance Compare the aplitudes of the power supply voltage to the voltage over the capacitor at resonance. Note the phase shift.
EM-k3b Dissectable Transformer Light a bulb and show voltage relationships with various coil and frequency combinations.
EM-k3a Transformer Demonstrate step-up and step-down transformers.

Chapter32--Maxwell's Equations; Magnetism of Matter

EM-g1a Lodestone Show that the lodestone attracts small nails and paperclips.
EM-h1c Dip Needle A dip needle is used to show the inclination of the earth's field.
EM-g3c Diamagnetic Glass A small glass rod suspended by a thread in the gap of a powerful magnet orients transverse to the magnetic field.
EM-g3e Floating Diamagnetic Graphite A piece of diamagnetic graphite floating on water is pushed around by a magnet.
EM-g3d Diamagnetic Levitator A small magnet is suspended in mid-air between two diamagnetic graphite disks.
EM-g1b Steel Bar and Magnet Puzzle Given only a cylindrical magnet and a similarly shaped steel bar, figure out which is which!
EM-g2c The Barkhausen Effect Clicking noises are heard when a magnet is brought near iron wire within a pickup coil.
EM-g2d Magnetic Domains in Ferrimagnetic Garnet Watch a ferri-optical garnet between crossed Polaroids on a microscope as a magnet is brought near.
EM-g2a Magnetic Domain Model An array of small compasses shows domain structures
EM-g5a Meissner Effect Cool a superconductor and it will levitate and float a magnet.
EM-g5b Hopkins Superconducting Model Maglev Train A model train with with two superconducting disks cooled by LN2 glides over a track of powerful magnets
EM-g3b Paramagnetic Aluminum A small aluminum rod suspended by a thread in the gap of a powerful magnet aligns with the field.
EM-g3a Paramagnetic Liquid Oxygen Liquid oxygen condensing from air drips into the gap of a strong magnet

Chapter33--Electromagnetic Waves

O-a1b Speed of light in fiber optic cable Compare the time for a light pulse to travel through two different lengths of fiber optic cable.
O-a1a Light Bulb in Vacuum Show a buzzer and light bulb in vacuum
EM-n1b Microwave Generation and Detection Show the generation and detection of microwaves including polarization
EM-n2a Tesla Coil Light a fluorescent lamp by holding it near a Tesla Coil
EM-n2c Large Tesla Coil Light a fluorescent lamp by holding it near a Tesla Coil
O-h1a Polaroids on the Overhead Show polarization with two or three sheets of polaroid on the overhead
O-h1d Vanishing Wall Put your hand through a "wall" created by a trick of polarization.
O-h1b Microwave Polarizing Filter Insert a grid of parallel wires (= cookie cooling rack) in a microwave beam and rotate the grid.
O-h3a Karo Syrup Insert a beaker of liquid sugar between crossed polaroids.
O-h3p Calcite Crystals Use a polaroid filter to show the polarization of ordinary and extraordinary rays
O-h3q Demonstrating Strain with Crossed Polaroids A set of lucite shapes are stressed between crossed polaroids
O-h5a Polarization in the Sunset Demo Rotate a Polaroid at the side of the tank in the sunset demo.
EM-n3b Project the Spectrum Project white light through a high-dispersion prism
O-a4a Magic Mending Solution A broken pyrex beaker is "magically" mended with a beaker of Wesson Oil.
O-a4d Refraction with Blackboard Optics A single beam of light shines on a large acrylic surface.
O-a4j Stick in Water A stick appears bent when inserted into the water at an angle.
O-a4s Total Internal Reflection (Blackboard Optics) Show total internal reflection with the blackboard optics kit.
O-a4p Total Internal Reflection-Fiber Optics Shows the path of a laser beam inside an acrylic rod.
O-h2b Reflection off Water Reflected light is shown to be polarized.


O-a1c Blackboard Optics -- Plane Mirror Use multiple-beam generator to show image formation with a plane mirror.
O-a1d Corner Reflector Look into a corner reflector
O-a1e Multiple Virtual Images By folding two mirrors hinged together, show multiple virtual images of a candle.
O-a2c Blackboard optics -- curved mirrors Show image formation (size, location, orientation) from concave and convex mirrors on the blackboard.
O-a2d Optic Mirage Two concave mirrors face each other. The top mirror has a hole allowing light to enter and escape. An image of the objects resting on the bottom of one appears at the center hole of the top mirror.
O-a2e Large Concave/Convex Mirrors Shake hands with yourself using the large concave mirror; view images in the large convex mirror.
O-a6a Blackboard Optics -- Thin Lens Ray trace images using convex and concave lens and a parallel ray box.
O-a6b Image formation with Thin Lens Project or view the image of an illuminated arrow through a thin lens.
O-j1c Working Eye Model A model demonstrates the focal capabilities of the normal, nearsighted, and farsighted eye.
O-j1e Eye Model (Blackboard Optics) Show normal, nearsighted, and farsighted blackboard optics eye models, and correct with additional lenses.
O-a6c Magnifying Glass with Eye Model Use the Working Eye Model to show a magnifying glass enlarging an object's image and allowing the near point to move closer to the eye. Greater magnifications can be achieved with stronger magnifiers.
O-a7a Microscope Model (Blackboard Optics) Mimic a microscope objective with blackboard optics.
O-a7e Two-Lens Microscope Model Use two lens to make a simple compound microscope.
O-a7d Celestron Telescope Show and tell the Celestron C90 telescope with Maksutov-Cassegrain optics, 90 mm aperature, 1 m focal length, and f/11 focal ratio.


O-d4a Michaelson Interferometer Show the Michaelson Interferometer and how it works.
O-d4b Michelson Interferometer and soldering iron Produce an interferogram of turbulant air with a soldering iron in the optical path of the Michaelson interferometer.
W-b5a Single Slit in Ripple Tank Diffraction from a plane wave passing through a single slit on the ripple tank mounted on the overhead projector.
O-c1a Single Slit Diffraction Pattern - Cornell Slits Shine a laser beam through single slits of various widths. The Cornell slitfilm is shown; we also have a slitfilm from Pasco
O-c1b Microwave Diffraction - Single Slit The diffraction pattern of a single slit can be heard with the audio-coupled detector
W-b5d Double Slits in Ripple Tank A plane wave impinges on a barrier with two slits in the ripple tank on the overhead projector.
O-d1a Double Slit and Laser - Cornell Slitfilm Use a laser bean on the slits on the far column of the Cornell slitfilm to show the effect of increasing the spacing between a pair of slits, with the slit spacing held constant. The first entry is a single slit.
O-d3a Newton's Rings Reflect white light off Newton's Rings onto a screen.
O-d3d Air Wedge Two microscope slides on top of one another produce interference fringes between them.
O-d3b Soap Film -- 2 Litre Bottle View the interference fringes of a soap film in a 2-litre bottle.


O-c2a Arago's (or Poisson's) Spot The diffraction pattern from a laser beam shining on a small ball has a bright dot in the center of the shadow of the ball.
O-c2e Pin hole diffraction - projected View the diffraction pattern of a pinhole; a variety of pinhole dimensions are available. The photo shows 100 um and 50 um round pinhole patterns and 100 um and 50 um square patterns.
O-d2a Number of Slits Shine a laser beam through various numbers of slits with the same spacing and width
O-d2c Types of Diffraction Gratings Transmission and Reflection, Blazed and Not, Diffraction Gratings of different line densities probed by a laser.
MO-b1a Diffraction Grating and Atomic Spectra Have students look through a diffraction grating at a spectrum tube.
O-d2h Diffraction from DVDs Light is diffracted from a CD and DVD
O-d2e 2D Diffraction - Pasco Patterns Show diffraction patterns from two 2D patterns, one square in symmetry and one hexagonal.
O-d2d 2D Diffraction - Optical Transform Kit Diffract laser light with this set of 32 patterns, mostly of 2-D lattices with various symmetries and lattice bases, available from
O-d2f 2D Diffraction - DNA Optical Transform Use this set of 12 grating patterns with a laser to teach the diffraction of DNA (slide also available from


Chapter38--Photons and Matter Waves

MO-a1a Photoelectric Effect in Zinc A charged electroscope attached to a zinc plate discharges when UV light illuminates the zinc.
MO-a6a Electron Diffraction Electrons passing through a carbon target produce a circular diffraction pattern.
MO-a5d Vibrating Circular Wire A circular wire driven by a function generator produces standing waves at resonant frequencies.

Chapter39--More About Matter Waves

Chapter40--All About Atoms

EM-h2d Precessing Magnetic Dipole A magnetic dipole floating in an air bearing precesses in a uniform B field.
EM-h2e Classical Magnetic Resonance Rotate a transverse magnetic field to "flip" the spin of a precessing magnetic dipole.
O-p6a HeNe Laser exposed Examine an exposed operating HeNe laser cavity with a diffraction grating.

Chapter41--Conduction of Electricity in Solids

EM-L3a Bridge Rectifier with LEDs Operate a bridge rectifier with LEDs at low frequency
EM-m1a Diode I-V characteristics Circuit for measuring the I-V characteristics of a diode

Chapter42--Nuclear Physics

MO-d1b Geiger Counter and Samples Listen to the counts from a Geiger Counter brought near to a radioactive sample.
MO-d3a Diffusion Cloud Chamber A diffusion cloud chamber shows the tracks from cosmic rays and from alpha, beta, gamma, and X-ray sources.

Chapter43--Energy from the Nucleus

Chapter44--Quarks, Leptons, and the Big Bang

Physics Lecture Demonstrations at the Department of Physics and Astronomy
The Johns Hopkins University