Crookes Radiometer - 7 inch tall

The Crookes Radiometer can show you in real time the impressive power of light. Inside the Crookes Radiometer is a rotor with 4 metal vanes. The vanes are silver on one side and black on the other. When exposed to light or heat, the black side of the vane heats up faster than the silver side, generating a small current of air that turns the vanes! The vanes spin faster as the light and accumulated heat on the vane gets more intense. A fascinating way to experience thermodynamics in action! It's a clear demonstration of real scientific principles of thermodynamics. Who knows, it may inspire the next Einstein! Just stick it under the sun and watch it spin!

Features:

• Demonstrates thermodynamic principles of heat transfer
• Differently-colored vanes absorb different amounts of heat
• Unequal heat distribution causes the vanes to spin without batteries
• Works with solar or indoor light
• An elegant but functional desk toy perfect for scientific demonstrations