19/06/2026
Three of my favourite gadgets: a Newton's Cradle, a Crookes Radiometer, and a Levitating Lamp!
Crookes Radiometers turn when light hits them, and (to my delight) there is *still* controversy about why they spin, 140 years since their invention.
The lamp emits just enough LED light to spin the Crookes Radiometer for several minutes at a time - a real surprise, because usually direct sunlight is necessary. These are very nice quality radiometers!
Of course, I had to capture the very cool levitating marble within the lamp that doubles as its on/off switch. 😁 Physics is so cool.