The solar radiometer demonstrates with simple physics and movement how light can be transformed into energy. The black and polished vanes are suspended in the semi-vacuum created inside the radiometer. When exposed to a warm light source, such as the sun or a lamp, the vanes spin. The more powerful the light source the faster the vanes will spin. The black side of the vane absorbs light faster than the polished side. Air pressure builds and raises the temperature of the air molecules on the back side of the vane causing the spinning motion.
The radiometer will not work with fluorescent light. In order for it to function properly, expose the radiometer to a spot light or natural light.
Exit9 is a superbly cool and incredibly diverse gift store specializing in museum quality items, designers goods, curious toys and, well.... FUN.
Stores in the East Village and Brooklyn -- Village Voice Best of NY 2010 -- Best Place to Buy Spur-of-the-Moment, Inexpensive Gifts for Virtually Anyone!