Corona discharge |
|
A metal point that is charged to 30 000 Volts or more will discharge into dry air. The discharge is accompanied by various forms of blue fire. The image below was taken at ISB with a 30 000 Volt induction coil in a dry box (in relatively dry air). The discharge was continuous when no metal objects were within the maximum spark length of 4 cm.
|
| Corona discharge in thunder storms from the tips of masts at sea and umbrellas on golf courses is called St Elmos fire. Scarry but harmless. |