I’m guessing many of you readers saw the ‘Sunday’ programme last Sunday. (Would be silly if were on another day of the week). Carlos Van Camp, the guy with the lightning show, was pretty impressive.
What was refreshing was how the whole piece was presented without mangling the science, which is something that media are adept at doing. Whenever I hear electricity talked about on TV, radio, in the papers, it’s probable that there’ll be statements about currents of 40 kilovolts, charges of 10 megawatts and so forth. Pick some random numbers, mix and match electrical sounding names with electrical sounding units, use them all entirely out of context, spice with health-scare comments, blame it all on the government (or the previous government) and you’ve got your story.
But not in this case – mostly, I think, because they let the guy himself do the talking.
I loved the lightning fighters – here you can see that the electrical discharge comes from the tips of the ‘swords’. That’s because the electrical field is greatest around objects that curve most strongly (i.e. pointy things – especially conductors). Therefore the air will break-down electrically at these points first, and it’s where a spark will originate from. That’s why a lightning conductor is the most likely point on a building to be struck by lightning – they don’t get hit just because they are taller than anything else, but because they have been designed to increase the electrical field around them and encourage a hit to them, not elsewhere on the building. You can also see the way the spark jumps about along different routes between the two sword tips.
I would be a touch concerned however, about the crowd standing so close. I would want very careful control of them. You wouldn’t want to find yourself accidently standing between the two guys.
If you haven’t seen it, you can watch it at the link above.