Corona discharge with a discharge current of a few hundred microamperes can blow out a small candle flame within about 1 cm of a discharge point. A pinwheel, with radial metal spokes and pointed tips bent to point along the circumference of a circle, can be made to rotate if energized by a corona discharge; the rotation is due to differential electric attraction between the metal spokes and the space charge shield region that surrounds the tips. Corona discharge A corona discharge is an electrical discharge brought on by the ionization of a fluid such as air surrounding a conductor that is
Eureka (word) Eureka (word) Eureka () is an interjection used to celebrate a discovery or invention. It is a transliteration of an exclamation attributed to Ancient Greek mathematician and inventor Archimedes. "Eureka" comes from the Ancient Greek word "heúrēka", meaning "I found (it)", which is the first person singular perfect indicative active of the verb "heuriskō" "I find". It is closely related to heuristic, which refers to experience-based techniques for problem solving, learning, and discovery. The accent of the English word is on the second syllable, following Latin rules of accent, which require that a penult (next-to-last syllable) must be accented if