Black Body Radiation Lamp
color/temperature - black body spectrum - electromagnetic radiation
What it shows:
The thermal radiation emitted from a black body is temperature dependant. The tungsten filament of a bulb
approximates a black body, and by increasing the current through the bulb, its temperature rises and so its
color spectrum shifts to shorter wavelengths.
How it works:
We use a 1000W GE bulb connected to 110V through a variac. Starting at zero you can gradually increase the
current through the bulb. You get a clear change from orange-red to orange to yellow before the bulb becomes
intense white.
Comments:
Limited by the characteristics of the bulb. It gets unbearably bright too soon to get a decent range of colors.
Any size clear bulb will do for this. Rating*
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