* = equipment from Mike Thomason = MT
Useful things to remember:
- GO20/30 face south - so instructor faces north.
So sides of room useful for NSEW
Test of Astrology
Omarr Reads the Stars
Get horoscope from yesterday's paper (Daily Camera's good)
Cut out horoscopes - separate signs+ dates - scramble. Number each.
Paste onto page and ask 3 questions:
Write down if horoscope read the day before Put number corresponding to sign in box Put number corresponding to best description of your yesterday in box
Gyroscope* (large, power-driven)Seasons
Shows spin axis pointing in same direction even when moved around
Analogy to Earth's spin axis pointing at Polaris
Add weight to show precession
GlobeDemonstrate spin with axis pointing towards Polaris
New York leads Los Angeles -> direction
Human (cut out and taped to globe) standing on Boulder -> orientation
Latitude = angle between Polaris and N. horizon
Hand-held pendulum + GlobePendulum continues swinging in same direction even if surface underneath rotates
Set pendulum swinging over globe and rotate globe to show how pendulum appears to rotate relative to person standing on the globe
Foucault Pendulum - in Gamow Tower - window from outside
Rotating Stage*Demonstrate pendulum - using large tripod pendulum*
Demonstrate apparent motion of stars have some students on rotating stage and students in audience as stars. Compare apparent motions seen by each.
Arm wavingStretched hand = 15° = 1 hour of rotation
Fist = 10°
Width of index finger = 1°
Width of little finger = 1/2° = angular size of Sun and Moon
Get all students to judge angular size of lights in ceiling
GlobeStand at varying distance from globe and show with arms how angular size varies as you move towards / away from globe
Sidereal vs. Synodic
Globe + overheadUse object on wall as reference star. Show how Earth/globe motion around the Sun/overhead leads to day relative to stars is shorter than day relative to Sun.Enactment
Synodic vs Sidereal month is harder. But you can use people to be moving Earth with Moon orbiting. Requires good 'actors' - TAs probably.
Gyroscope* + weightSet the power-driven gyroscope going pointing towards Polaris.
Add weights -> precession
Moon Motions / phases
"Moon on a stick"Ideally, give each student a polystyrene ball on a stick (about 50 available in Dept) and turn off all lights except one central light.
Moving ball on stick around one's head (Earth) dramatically illustrates phases.
Fruit - particularly cantaloupe - in sunshine also works well.
Use a paper plate to show that a disk does not work - Greeks worked out the Moon had to be a sphere illuminated by the Sun.
Globe + ball / fruitAdvantage of fruit = novelty (= memory) - and it usually has a "feature" which can be used to be the "face" of the Moon - or non-spherical -> bulge.
Move Moon around globe -> "phase lock" (orbital = spin period)+ third object (e.g. overhead) as Sun to show lunar vs. sidereal month
Hula hoopOrbit of Moon - tilted 5 degrees with respect to the ecliptic
Nodes - line up -> eclipses
Eclipses to ScaleThis is hard - Colorado Model Solar System scale has Sun about 10 cm (= grapefruit) which puts the Earth as 1 mm (grain of rice) at about 20 m.
Making realistic shadows is very difficult due to scattering of light in room.
BlinkingGet each student to hold finger up and blink.
Move finger farther away / closer -> appear to move more or less?
Pick object / person across room - move head side to side.
Extend baseline to walking distance.
Planetarium = bestNewton's laws of motion & GravityShow retrograde motion of Mars using annual motion only.
Show relative motions using orrery.
Ptolemy vs. Kepler -JAVA applet demonstration - needs PC running windows + Netscape 4.0
http://solarsystem.colorado.edu - go to Kepler Module
Newton's laws of motion - cabbagesAbout 1 kg each - illustrates a kilogram
Apply a force -> accelerates (throw cabbage across room)
Apply bigger force - accelerates more (goes farther across room)
Take smaller object (onion?) - less force needed for same acceleration
Newton's third lawBalloon rocketNewton's law of gravity - cabbages
Skateboard - unless you have a large, stable skateboard or a "dolly"*, this does not work very well. Bricks* wrapped in towels to throw off the back.
Force between 2 cabbages (one red, one green?)
Force between cabbage and Earth
AccelerationGravity applied to cabbage -> drop -> accelerates
Drop 2 objects (red & green cabbages) from balcony
Drop sheet of paper. Crumple up into ball and drop
OrbitsBalance of centrifugal and gravitational forces - Eraser on a string - twirl around head, let go.
Into orbit - throw object across room, throw harder -> farther (argue if thrown hard enough it would not hit the ground until over horizon where Earth curved down. Harder again -> orbital velocity, orbit)
SpectrumOverhead or incandescent bulb* + hand-held diffraction grating -> ceiling
Projection through a grating onto screen*
Colored objects - e.g. planetsColored card & transparencies with overhead -> reflection, absorption and transmission of light in different parts of the visible spectrum
Black / white card -> albedo
Wein's LawElectric stove / element - shows bright orange to deep red (to "heat" = IR)
Incandescent lamp on rheostat*
Rigel vs. Betelgeuse - slides of Orion & spectra
Stefan-Boltzmann LawIncandescent lamp on rheostat*
SpectroscopyTransmission gratings for each student* (about 1" square)
Gas discharge tubes* for different gases.
Compare with incandescent and fluorescent lamps
Atomic (simple) vs. molecular (complex)
TelescopesLarge lenses + light source* to show light gathering + focus
Curved mirror* + light source
Cassegrain - SBO
Properties of Planets
DensityPaper cups filled with different materials (e.g. sand, lead weights, polystyrene chips, water) labelled with density -> "feel" for range in density.
AgeRadioactivity - everybody stands up, each toss coin. Heads sit down.
SpectraSlides of Jupiter and human in both reflected sunlight and thermal IRViscosity of rock
Reflected sunlight and thermal glow -> double hump
Solar spectrum above atmosphere, on ground
Thermal emission of EarthLava lamp
Powers of Ten - Shows scales of universe in 40 orders of magnitude. Depending on version, may need to fast forward to the actual annimation (10mins)
Seasonal Dance - Shows seasonal changes in vegetation, snow and ice coverage as sub-solar point moves in latitude with the seasons. (7 mins)
Apollo - Shows astronaut dropping hammer on the Moon.
Shuttle video of "weightless" astronauts?
Hubble launch & refurbishing missions