Fluorescein v. Laser Frequency
Need a laser pointer? Incredibly, you can get 3 (one of each color) for under $20 (including S&H):
From Amazon: BUY NOW Red+Green+Purple Laser Pointer
Make you own fluorescent solution with this powder:
From STEMCell Science: BUY NOW: Fluorescein Powder
Fluorescein v. Laser Frequency: exploring how this famous fluorescent dye reacts to three frequencies of laser pointer using this unique liquid filled paperweight. Under Green (532 nm) we see some mild yellow fluorescence as the beam transmits through the liquid, under Red (635 nm) the beam transmits with no reaction, but under near UV Blue (450 nm) the beam is completely absorbed near the liquid surface and re-emitted in bright green with a peak at 515nm. A fun home experiment to explore quantum physics phenomena with inexpensive apparatus.
Neon Flicker Flame Night Light
Similar old fashion flicker bulb lights available here:
From Amazon: BUY NOW Flicker Flame Neon Bulb
Get this diffraction grating here to explore light source spectra:
From Amazon: BUY NOW: 500 line/mm diffraction grating
Neon Flicker Flame Bulb: this charmingly designed night light evokes a theme of an old fashioned gas street lamp- however there is no flame, but instead the light is due to emission spectra from excited neon gas as a result of a discharge electric current from the 120V house mains. The flickering effect comes about because the current flow will increase the temperature near it, which raises the pressure and affects/raises the breakdown voltage near the current- so the glow from one area can only last as long as it takes to heat up and raise the breakdown voltage which then briefly kills the current in that area. In other physics, a diffraction grating shows that the gas is indeed neon, which only emits light at specific emission wavelengths- mostly reds with some bright yellow lines (and a clearly visible green line) at AC house voltages.