An ordinary pickled gherkin is fixed between two forks that are connected to the mains via a special dimmer switch. Two red and two green high power LEDs are inserted into the gherkin. With the help of the dimmer it’s possible to make the green LEDs glow at one time and the red LEDs at another time. After that the dimmer is turned to its maximum output (220V) and the gherkin starts to sizzle and to smoke until it is glowing yellow.
How does it work?
The gherkin can be electrified as is contains a lot of salt and is therefore highly conductive. Although the gherkin is connected to a considerably high voltage of around 100V, the LEDs are not damaged. This is due to the potential gradient between the forks, resulting in a voltage of only 5V or so being applied to the poles of the LEDs.
Since the special dimmer delivers only direct current and the LEDs are only conductive in one direction, the red and green LEDs can be positioned in different directions so the colours can be ‘switched’ on individually just by changing the direction of the current.
When full voltage is applied the gherkin becomes so hot that the water and the salt inside vaporize. Subsequently a plasma forms and the sodium ions emit yellow light.
