Crookes Radiometer, Lightmill Model No.: CR-60110BLT Products Category : Crookes Radiometer INQUIRY Details See video as : Originally, designed by William Crooke in the 1860's, the radiometer still fascinates both young and old. The Crookes radiometer, also known as a light mill, consists of an airtight glass bulb, containing a partial vacuum. Inside are a set of vanes which are mounted on a spindle. The vanes rotate when exposed to light, with faster rotation for more intense light, providing a quantitative measurement of electromagnetic radiation intensity. The reason for the rotation was a cause of much scientific debate in the ten years following the invention of the device, but in 1879 the currently accepted explanation for the rotation was published. Today the device is mainly used in physics education as a demonstration of a heat engine run by light energy. It was invented in 1873 by the chemist Sir William Crookes as the by-product of some chemical research. In the course of very accurate quantitative chemical work, he was weighing samples in a partially evacuated chamber to reduce the effect of air currents, and noticed the weighings were disturbed when sunlight shone on the balance. Investigating this effect, he created the device named after him. It is still manufactured and sold as an educational aid or curiosity. Send Inquiry Name:* E-mail:* Tel: Content:* Verification Code:* (All * must be filled in) [ Previous:CR-60110AMT ] Related Products Crookes Radiometer, Lightmill (Twisted Base) CR-T60190BLT (Twisted Base) Crookes Radiometer, Lightmill, Physics experiment CR-75215BLT Crookes Radiometer, Lightmill, Physics experiment CR-60110T Crookes Radiometer, Lightmill (Twisted Base) CR-T60190GRT (Twisted Base) Crookes Radiometer, Lightmill ,Physics experiment CR-60110TAM Crookes Radiometer, Lightmill (Twisted Base) CR-T60190TAMT (Twisted Base) Crookes Radiometer, Lightmill, Physics experiment CR-60110TAMT Crookes Radiometer, Lightmill (Twisted Base) CR-T60190TBLT (Twisted Base)