Video : Shake Flashlight - You Won't Need to Buy Batteries Never Again
Url :
Embed :
Related videos :
Embed :
Related videos :
This flashlight is based on Faradays Law of Inductance: a magnet passes back and forth between a wire coil giving charge to capacitor that powers the LED. Nice thing to have in emergency situations.. It is even good for exercise ;)
Tags : video led diy batteries magnet lamp how flashlight shake capacitor coil torch faraday inductance
