The simplest way to measure high voltage is by spark length ... is in units of atmospheres and the spark length is in millimeters. Most hackers work at atmospheric pressure which is 1 atm ...
We’d measure a doll house in centimetres ... and millilitres and litres are used for volume. 1 cm = 10 mm 1 m = 100 cm 1 km = 1000 m 1 cm is about the width of a staple 1 m is about the width ...