A gorgeous, fully-functional, hand-blown glass radiometer. Also known as the "ight mill" or "solar engine," the solar radiometer demonstrates with simple physics how light can be transformed into energy. Its invention in1873 is credited to Sir William Crookes, an English physicist. The black and polished vanes are suspended in the semi-vacuum created inside the radiometer. The vanes, or wings, in this solar radiometer are alternately dark and light in color. When the light strikes these wings it transfers heat to each one - but not at the same degree. The lighter wing reflects the rays and the darker wing absorbs. The stronger the light, the more energy there is to heat up the darker side of the wing, as air pressure builds and raises the temperature of the air molecules on the black side, causing the wings to spin faster. It spins under natural light of the sun, or a strong light concentrated upon it. Great for science projects, as a gift for a physics instructor, student, or enthusiast, or as an elegant conversation piece for your desk!
The large realistic model has removable organs that can be studied and set back into the correct position.
NEW 2016 DESIGN! This hip red tee features Pi to 1000 decimal places on an ultra soft 100% cotton shirt.
Command robotic creations with this cool construction kit!
This caffeine molecule mug makes an excellent gift!
Build your very own smart robot!
This glass Erlenmeyer mug makes an excellent gift!