{"product_id":"orange-solar-power-crookes-radiometer-solar-energy-spinning-b07mp6sss1","title":"DORAMI Crookes Radiometer, Solar Powered Glass Spinning Vanes, Orange","description":"\u003cp\u003eThe DORAMI Crookes radiometer is a handmade glass bulb with four vanes on a shaft that turn whenever light reaches them. You set it on a sunny windowsill or under a desk lamp and it spins with no batteries and no plug. It suits a science classroom, a home office or anyone who likes a desk piece that moves.\u003c\/p\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eBrand: DORAMI\u003c\/li\u003e\n\u003cli\u003eType: Crookes radiometer, light powered\u003c\/li\u003e\n\u003cli\u003eBuild: handmade vacuum glass bulb\u003c\/li\u003e\n\u003cli\u003eInside: rotating shaft with four vanes\u003c\/li\u003e\n\u003cli\u003eColor: orange\u003c\/li\u003e\n\u003cli\u003eLight sources: sunlight, artificial light or infrared\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWhat the radiometer shows\u003c\/h2\u003e\n\u003cp\u003eInside the bulb, most of the air is gone. Light warms the vanes unevenly, and that uneven heating gives the shaft a small push. Brighter light means a faster spin, so on a clear day your radiometer races at noon and slows when a cloud drifts past. At night under a reading lamp it turns at a calmer pace.\u003c\/p\u003e\n\u003cp\u003eTeachers use one to start a talk about light, heat and vacuum. Students can move a flashlight closer and farther away and watch the speed change, then compare a window at morning and afternoon. The maker lists refraction, air friction, light in a vacuum and uneven heating as principles the glass windmill can help explain, which gives a physics class plenty to work with.\u003c\/p\u003e\n\u003cp\u003eAt home it reads as a small curiosity on a bookshelf. Guests ask what powers it, and you get to explain. It also makes a thoughtful gift for a colleague, a graduate or a friend who likes science.\u003c\/p\u003e\n\u003ch2\u003ePlacement and care\u003c\/h2\u003e\n\u003cp\u003eSet the radiometer on a flat, stable surface, since the glass can shatter if it tips. A windowsill, a desk near a lamp or a shelf that catches afternoon sun all work. Dust the bulb with a soft dry cloth and keep it out of reach of small children and pets that might knock it over. Avoid hot surfaces like a radiator top. If the vanes stop, check the light first, because the radiometer needs a fair amount of brightness to start turning.\u003c\/p\u003e","brand":"DS-AMZ","offers":[{"title":"Default Title","offer_id":50654351851760,"sku":"AMZ-B07MP6SSS1","price":69.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0434\/7985\/9361\/files\/614rIkz-MgL._AC_SL1500.jpg?v=1792809643","url":"https:\/\/www.bigfrenchies.com\/products\/orange-solar-power-crookes-radiometer-solar-energy-spinning-b07mp6sss1","provider":"BIG FRENCHIES","version":"1.0","type":"link"}