7) Light

a) General

Four mirrors mounted on a rotator to simulate the first experiment to determine the speed
of light. Shows dispersion of white light into the rainbow colors. A prism shaped chamber that can be filled with different fluids. b) Geometric Optics A large wood box with a mirror mounted inside to produce a real image of a light bulb. A matched set of parabolic mirrors that form a real image of a needle that seems to float
above the box. A 15 inch Converging lens that Can project a 3 foot real image on a wall 40 feet away. A matched set of 22 inch mirrors Mirrors or lenses can be set up on the bench to show the different cases of object position
and the image produced.(Real, Virtual, Reduced, Inverted,or Erect images) A simple microscope set up on an optical bench using two lenses. A simple lower power telescope set up on an optical bench using two lenses. The properties of lenses made from air can be studied by inserting them in this tank of water
(they act opposite of glass lenses of the same shape). A convex lens that can be filled with different liquids to change its focal length. A flat mirror that can be bent into a fun house type shape. Shows the reflection of light from a candle on a glass sheet.
Two candles appear to be burning but one of them is not lit.
A good example of how Disney World does a lot of their tricks. Show how multiple images are produced in mirrors and kaleidoscopes.
Also shows an image that is not reversed left/right if the angle between the mirrors is 90. Shows light rays as they interact with lenses and mirrors of different shapes.
The individual rays are projected on a 2' X 3' backboard so students can see easily the
reflection and refraction. Shows a real application of internal reflection with a prism set from binocular lenses.                           Shows internal reflection of a laser beam off water/air interface (shows critical angle) A Plastic Pipe wrapped in a coil to show transmission of light through light pipe. Shows Astigmatism as an image spread out by one cylindrical lens and then corrected by
a second cylindrical lens. Place glass rod over words written in different colors (red and blue ink).
Some letters will flip upside down and others will not based on whether they have axial
symmetry.
Write letters that flip over in red and letters that don't in blue and ask students if the cause
Is due to refraction indexes or something else.
Great puzzle for students to figure out. c) Interference and Diffraction Shows light wave interference and how it can be used to measure minute distances
(this is tricky to set up give me an hours notice) Shows thin film interference created by the air gap between two glass plates.
It can be projected on a screen. Shows thin film interference in a soap bubble.
The colorful image can be projected on a screen and it has a speaker behind it to cause
standing waves in the film. Toy bubble maker for the fun thin film Toy for thin film High quality thin film interference filters. A simple toy to show thin film interference. Two speakers mounted on a stand that produce the same sound, they can be rotated so
Students can hear the interference pattern. Shows nodal/antinodal pattern created by two sources using overlaid transparencies of
Concentric rings. Can be used with the mercury , sodium, or laser light sources to project a line spectrum or
An interference pattern. Small slides students can look through to see line spectrums Funny looking laser light glasses that are actually created using a diffraction grating cut
horizontally and vertically.
A good challenge for students to explain. Shows diffraction of light across a straight edge but it is very sensitive and sometimes
Difficult to see. Shows a simple diffraction grating made from candle smoke on a glass slide with slits
Created by a razors edge.
Look through the slit at a straight filament for the diffraction pattern. d) Holography and Lasers Shows an example of a laser and chalk dust can be used to view the beam. Shows the inside of a laser as the tube is working ( this will not produce a beam but
Glows nicely) Examples of laser tubes and related power supplies A pair of safety goggles that are designed to absorb HeNe laser light Leslie smiles and winks as you walk past Shows Lissajous Figures produced by a mirror mounted to two speakers. Different types of bathroom glass produce interesting pattern when a laser is shone
Through it. e) Light Sources f) Colors A rotating disk of colors that blend to white if the speed is fast enough Shows the mixture of red, green, and blue lights produce white light.
Cyan magenta and yellow can also be seen Shows subtractive mixing of colors Two clothes that look exactly the same under sunlight but look different under fluorescent
Or incandescent light. Shows 1st, 2nd and sometimes 3rd degree reflections in a spherical water drop to produce
Rainbows.
A laser is reflected through the bottle Color Xerox copies of the plates from the textbook.
Shows primary color mixing, line spectra, reflectance graphs color image printing
And the CIE diagram Using a heating coil (or lamp) thermocouple and digital meter this demo shows IR
Absorption and visible transmission of radiation through glass and plastic filters of
Various colors. Shows afterimages and complimentary colors when students stare at colors shapes and
Then switch to seeing a white screen. Shine a slide projector through the gaps created by rotating a triangular wheel through the
White light Shows reflection of red and transmission of green light. Show the relationship between temperature and color as the variac slowly increases the
Intensity of the clear light bulb Shows polarization of light using some optical active substances like scotch tape, mica
Sugar solution, Plexiglas, under stress and calcite crystals with birefringence properties                           Shows how blue skies and red sunset occur by scattering light rays.
                          A solution of HCl and Sodium thiosulfate reacts creating a fine particulate that scatters
                          Blue light and passes red The red, green, blue light of the TV can be blocked to show color mixing or shadows. DR Detweiller devised this system to show light intensity and afterimages using cardboard
Masks in slide projectors.
This requires you practice for about an hour before you use it. A slide projector's white light, HeNe laser and a solid-state laser are all shown through
Gratings to diffract the light.
The wavelength of the two lasers can easily be seen to be different because they appear
At different spots in the full spectrum from white light. He Ne laser light at -632nm and solid-state red laser light at -670nm are directed into a
Glass of liquid vanish and one is absorbed while the other passes right through Large Charts of the visible and total EM spectrum