Lecture Master List
Ping pong ball nuclear reaction: 2 or 3 balls per person in the room....hit throw
Coin Flip Radioactive decay model, needs 200+ people
Balloon model of solid, liquid, gas.
Frictionless airpuck human (fire extinguisher)
frictionless airpuck, CD with balloon
air bubble in tube
candle in a jar in freefall
drop a slinky what does the bottom do?
drop a slinky it expands like an astronaut's back
Ball bounce recording
falling frame balloon burst (Tien)
strings and weights on pie pan (A)
dart gun and washer
distance versus time (run bike drive) )(A)
rolling acceleration (A)
Human bowling ball collision pendulum
orbiting coin inside balloon (2 coins mate) pop - radioactive decay
tennis ball on basketball launch (superball)
raquet ball cut bend launch (hopper popper)
Force on climbing rope with scale
drop basket type coffee filters (fluids)
Falling stick (1 end on floor other end a > g)
Inclined plane with a car jack
falling 2L bottle with holes
whirl a bucket of water overhead
water pressure collapse
Soy sauce Cartesian divers
floating aluminum coins Crystal structure (A)
falling basket coffee filters
center of pressure of plane
soap convection in milk (A)
Bernoulli bottle with tygon u-tube manometer (A)
Flubber recipe (A)
Float a potato in salt water under fresh water
oil will form a ball floating in water under isopropanol
entrainment blow a toilet paper roll with a blower
Balloon in a 2 Liter bottle with hole
fill it with water
visual convection tray of flow vis over hand
Clear plastic case of CO2, butane lighter burns high above top of CO2
mist poured from beaker of dry ice and water floats on the surface of CO2
like a cloud layer
float bits of dry ice on a water surface, comet like
Hole in a bubble
make an airplane from a styrofoam plate
bag whirly, blower
short slinky on fish line
short slinky spun from top, hung vertically
bicycle tuning fork (A)
phone cord pulses, resonance
mug of foam
Luisa's halftone sound model
lightly hold a balloon to feel sound (in sound column)
straw oboe, sound vs length
Ken's straw music
string over hands over ears (pluck it, stroke it)
binaural stethoscope sound intensity comparator
Breathe Sulfur Hexaflouride
Bang two 5 L plastic water containers together then hold the open ends next to your ears.
flying charged bubbles
charged tapes (A)
balloon zap (A)
A battery dissection (A)
magnetism, AC with pick-up coil
disposable camera electronics (A)
High voltage (A) 9v battery pile
make a speaker
sound transmitted by light waves
listening to IR transmitters
Magnetic accelerator from Michel Junge (Newton's balls)
magnet collision on pencil, use multiples.
Shawn's levitation magnet over copper slab
Digital Audio tape (A)
Peirson Oscillators (A) Big or small on overhead
magnets on a pencil (A)
magnet collisions on a pencil (A)
magnets round the rim collisions (A)
magnets round the rim symmetry
define a north pole (multicultural) (Tien) (A)
simple poles (likes repel) (A)
magnetic poles advanced broken magnets, magnets side by side (A)
magnetic balancing act opposed on finger tip (A)
magnetic shielding (Tien) use cover of Klutz book
magnetism force vs distance (A) digital scale
earth sphere with magnet and magnaprobe (A)
projection magnetic dip (A)
magnetic model of electric current (A)
floating magnets (film can) (A) Garden of Magnets
air table magnets
Barkhausen effect, pick-up coil, cow magnet, radio shack amplifier
eddy currents open channel
magnetic levitation over spinning disk
Tien's Revolution (Tien)
Tien's film can iron filing magnetization model (Tien)
Magnetic field viewer paper
Nd attracts paper money
Canadian coins are magnetic (K)
recent English coins are magnetic
bashful coins (K)
Magnetic cannon (K)
magnet stack shot out of donut magnets (K)
guided magnetic roller roll Nd along aluminum channel
silent collisions (K)
magnetic pendulum strange attractor (K) On book cover
magnetic tug of war (A)
magnets 1 vs 3 (A)
Magnet rings even and odd magnets (A)
Suspense explainer (A)
Extract iron from cereal
magnetic orbiter, Nd slides on rotating inclined Al disk
Curie point coins
Magnetizing iron (hold a paperclip on a fork) ( K Explorabook)
the birth of a paperclip (K)
magnetic fluid from burned steel wool or magnaflux powder (Eric)
Paper clips in a bottle pulled up by magnet under lid
filings from VCR tape
magnetic feedback and frequency shift.
image walk (A)
antigravity mirror (A)
plastic on table (A)
finding images with foamcore straws and tripod (A)
Image made by a cylindrical mirror (A)
image in ulexite
image in a hologram
light comparator (A) wax, plastic, grease spot
solar brightness vs 200 W bulb (A)
Camera dissection (A)
camera strobe and sound trigger
Fluorescent vs incandescent with comparator
minimag activities (A)
multi-shadow with holder and anti hole
dim maglite in a blindspot
diffraction naked eye, 3 x 5 card
dim minimag and retina
inverse square perf board
shadow through a frosted bulb
fresnel lens (A)
find the image
make an image on a mirror with a fresnel
pupil mirror bug-box
rainbow dust (A)
soap film on a film can (A)
spectra diffraction grating
slit under anti-slit
U-V detector cards
bend a beam of light laser through water over clear karo
RGB LED (A)
Bubble color (A)
polarization puzzle (squares with polarizer along the diagonal
Laser through a light bulb (x-ray shadow)
pinhole in film can (A)
1 pinhole vs 3 pinholes in filmcans
Gray Step (A)
Laser Speckle (A) (laser into frosted bulb)
Master eye (A)
Blacker than black (A)
how many moons in the bowl of the big dipper
after image size illusion
person vs distance size illusion
Hewitt's 2 eye vs 1 eye view hands at full distance 1/2 distance
Benham's disk on overhead (Centered top)
spiral on overhead
photo frame ripple tank
string thing (Don)
phone cord waves
giant slinky waves
group velocity make overheads with dark bands, and enlarged 10%
move them together or one faster, note group velocity
solar power vs 200 W bulb (A)
give and take, black pens and overhead (S)
conduction, propagation of heat and warmth with depth slides
convection, lamp, hands (A)
radiation, globe and sunlight (A)
seasons flat or wrapped around cylinder
Cloud in a bottle use a bike pump and isopropyl
match in water provides soot seeds and ion seeds too
balloons in a dewar
break a penny
freeze flowers in a dewar
break a frozen hot dog
hot dog in a playtex glove (break it )
make liquid oxygen and pull onto a magnet
Radioactive Decay - audience coin flip and clap
RGB LED's (true green and bright blue)
Radioactive decay model (phosphorescent paint brightness)
Spin a Koosh (A)
Tide model (A) (E)
Magnet stack model of earth atmosphere
map projection (A)
timing earth rotation (A)
self-centered globe light distribution and temperatures by hand
sea floor spreading model with magnetic tape strips
minimag and thermal postcard model of Hawaiian islands
Projection diffraction grating
fraunhoffer lines with holographic diffraction grating and thin distant slit,
expanding Universe overhead (star field and star field enlarged 10%
Circumference vs height of glass (A) (E)
toilet paper tube height vs circumference (E)
8.5 x 11 paper cylinder volumes (E)
deflection of beams
deflection of floor or wall (mirror laser beam)
milli can coins in film cans
Take it from the top (A) with cassette boxes
Descriptions of the activities
Whiled Music, the Science of corrugated tube sounds.
I play music on an assortment of different size corrugated plastic tubes by whirling them around in circles. Between playing the tubes I tell stories and do activities which show the science behind the singing tubes. I can play tubes up to 12 feet long and 6 inches in diameter, if the stage is large enough. I also play the bag whirly, a corrugated tube with an inflated garbage bag on one end &emdash; it is played like a bagpipe by squeezing the bag under one arm.
I ride a disk which slides without friction on a cushion of air. A battery operated leaf blower blows air into the disk. I hold a Carbon Dioxide Fire Extinguisher and use its blast as a rocket propulsion system.
Breathe Sulfur Hexaflouride, Breathe Helium
I breath helium from a balloon the frequency of my voice more than doubles.
Then I breathe sulfur hexaflouride from a balloon, which by the way behaves like a lead balloon, and the frequency of my voice is lowered to less than one-half.
Air bubble in tube
I have a 1 meter long, 2 inch diameter clear plastic tube with water and a 2" diameter air bubble inside it. The bubble floats to the top of the tube. Let the bubble rise to the middle of the tube and then drop the tube and the bubble stops rising. The air in the bubble and the water in the tube fall together in free fall. Let the bubble rise to the middle of the tube then throw the tube into the air keeping it vertical and the bubble does not rise even when the tube is going up &emdash; the tube is in freefall even when it is going up. Hold the tube horizontal extending in front of you then spin around and the bubble comes toward the center of the circle of your spin.
Candle in a jar in freefall
Place a lit candle in a jar. Drop the jar. The candle goes out quickly. In freefall the oxygen depleted gas around the candle is not removed by convection.
Human bowling ball collision pendulum
While standing on top of a ladder, and belayed from above. Pull a bowling ball to your chin and release it. The ball will swing away and return but due to conservation of energy not hit you. The citing the need to test the symmetry of this experiment. Fix the bowling ball in place and swing away from it and back on the belay rope. Then, as a super collider the bowling ball and I swing away and back together at the same time.
Force on climbing belay with a scale
A climber hangs from a scale capable of reading 300 pounds. He holds both ends of a rope from the scale. The scale reads 150 pounds. The climber hands one end of the rope to another person to belay him and the scale reads 300 pounds.
Inclined plane with car jack
I stand on an inclined plane as another person jacks up the end of the plane with a car jack. When the angle gets steep enough my shoes slide down the plane. The tangent of the angle of the plane from horizontal tells me the friction coefficient of my shoes.
Whirl a bucket of water overhead
I have a water bucket and whirl it in a vertical circle over my head. The water stays inside the bucket. Then I put the bucket down and pick up another bucket full of glitter. When I stop the bucket over my head I get a bath of glitter.
Spinning cylinder (Not for large audiences.)
A piece of PVC pipe is spun and rotated at the same time. If it is marked at on end it produces patterns of marks. A tube cut three diameters long produces a triangle of marks. Spin the tube from the other end and the marks vanish.
Collapse the can
Boil a small amount of water in an empty one gallon can. Take the can off the heat and immediately close it, it must be airtight. As the can cools it emits popping noises and eventually suffers a sudden collapse as the water vapor inside the can condenses leaving a partial vacuum in the can.
I can also collapse a 55 gallon drum. Add 2 liters of water. Boil it for 5 minutes. Turn off the heat, and then seal the can. It will collapse explosively.
You can boil water in an aluminum soda can, then invert the can in cold water and it will explosively collapse.
Floating aluminum coins (for large audiences on an overhead.)
I float aluminum coins in a tray of water. The coins are denser than water but are suspended by surface tension. Two nearby coins seems to attract each other moving together to form a coin dimer. Many identical coins come together to form a hexagonal closest packed structure.
Falling basket coffee filters
Basket type coffee filters fall stably and slowly.
Race a stack of 2 filters against one. Measure the height from which the two must be released in order to arrive at the ground at the same time as the single one. The double mass filter must be released from a height of 1.4 times the single one, i.e. the square root of 2 higher. This is because the air resistance is proportional to the square of the speed of fall of the filter. A quadruple mass filter must be dropped from twice the height of a single, while 9 nested filters must be dropped from three times the height of a single to reach the ground at the same time.
Float small bits of dry ice on the surface of a tank of water with a dark bottom. The bits of dry ice skitter about leaving a spinning trail of mist behind like the tail of a comet.
Hole in a bubble (small group demo)
Make a large bubble. Tie a loop out of string, leave a tail of string. Wet the string in bubble solution. Place the string on the bubble, keep hold of the tail. Puncture the bubble within the string and the surface tension of the bubble will draw the string out into a circle. The hole can then be moved around through the bubble film.
Ringing Aluminum Rod
I have a 1.5 meter long solid aluminum rod 1.5 cm in diameter. By striking this rod on the end while I hold it in the center I can make it resonate at its fundamental frequency. It rings for a very long time, for over a minute. Grab the rod at the end and it stops ringing, grab it near the middle and it doesn't stop ringing. How fast it stops ringing tells you how much it is moving at that point. The faster the sound dies away the more it is moving. So you can map the vibrational motion of the rod with your fingers. Hold the rod 1/4 of the way from one end and it will also ring for a long time, or 1/6 or 1/8. Map out the pattern of motion of these harmonics. There are also sounds due to bending of the rod. Strike the rod sideways at the end and excite the fundamental mode of bending which has a lower frequency.
Hold a slinky by one end and allow it to hang vertically. Drop the slinky and observe what happens to the bottom. (It remains at rest initially) The top meanwhile accelerates down with an acceleration greater than g.
Compress a slinky, then drop it. It will expand just like the spine of an astronaut.
talc in blanket for egg throw. poof white.
pop can to indicate slinky motion. pulses add to double motion.
red hose full of water, wrap with retroreflector tape.
Scientific Explorations with Paul Doherty
25 May 2004