Chapter One Demonstrations

READING: Seeing the Light, pp. 3-27


The SPECTRUM of ELECTROMAGNETIC RADIATION

Shaking the forever flashlight induces a current as the magnet moves through the coil.

Which of the objects below have nothing to do with electricity or magnetism?

Junk with coils and magnets

A silicon photo-cell makes the infrared pulses emitted by the remote control visible on the oscilloscpe.

Remote control aimed at a detector wired to an oscilloscope

X-rays make my fillings visible.

Toothe X-Ray


SOURCES OF LIGHT

The shorter wavelength Ultraviolet light excites the paint pigments into Fluorescence at longer wavelengths.

Black light excitation

Next time I paint these cards I will use a black background for a more satisfying black light poster experience!

The word OPTICS in Day-Glo colors

High voltage from a Tesla Coil excites the Helium and Neon atoms in the laser tube to emit their unique spectra due to Atomic Transitions. The atoms in the air do it, too!

A Tesla Coil stimulates a laser tube into emission

Collage of light-emitting junk

Sometimes Photoflood bulbs use blue jackets to raise the color temperature by reducing the red end of the spectrum.

Blue bulb

EYEWITNESS DEMONSTRATIONS:  Recall what you saw.
Why does chalk dust make a laser beam visible?
How did Michelson's speed of light experiment work?
Why did the Radiometer spin?
What are the similarities and differences between electric motors and generators, microphones and speakers?
What are the two major types of controls on an oscilloscope?
What do you see when the remote control is directed at the IR camera?

Back to Optics Museum Index

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