Lightning, laptops and monitors ...

I rarely do but, I do take into account the advice that someone in here tried to get across, a long while ago. If either the energy in the sky is reaching down to the earth or, vice versa, does the the device connection with the earth mean the earth potential is within your device? Does the height of the connected device matter?

The heavily charged atmosphere passing through may take a liking to it.

If you imagine all the earth wiring around you, you can imagine you are sitting in a lightning tree. Which might be a comfort if you have just taken your iron supplements.

My only comment would be, be careful what you wish for.

While there are the maths and analysis for predicting what will happen, lightning is fickle and every once in a while, defies theory. Ask some particular golfers about this (they attract lightning). They're scared shitless, because of their luck. Iron supplements or no.

And if you're going to stand under a tree while this is going on, stand with your legs tangential to the trunk of the tree. Don't stand on a radial line with respect to the tree. This will help protect you from having your balls burned. You can still sustain other kinds of damage. People sometimes have a small hole punched in their hand, where a secondary discharge entered. And then depending on luck, there could be another hole where it leaves.

Paul

Plus the extra holes where the bark flies from the trunk of the tree propelled by the steam explosion. I have seen an oak tree where the trunk was turned to splinters by a lightning strike and the tree fell. Splinters were found over 100m away.

John

Many years ago, walking across Harrow Hill one (probably Friday :) ) evening, I paused with some friends to light a cigarette. It was a dry summer night, and we were on the path - about half way up.

From nowhere, a flash of lightning struck a tree about 20m away. Enough to sizzle it (but not catch fire).

Not sure why it did this when there was a church with a steeple and lightning conductor a good 100ft taller right next door.

Well its like RF and radio waves not that well understood so called Black Magic by most.

Course theory exists for lightning discharges, its a very complex combination of the DC and AC components resistance's and inductance's in the ionised air..

In broadcast engineering they think some old timers that tying knots in cables "kills" the lightning they are simply introducing an inductance that will block HF parts of the discharge inside of a building etc..

Like that of bring the down conductor behind a gutter rather than over and round it that introduces a significant inductive part to the discharge path..

Yess.. Where's old w_tom AKA Mr Lightning got to these days?, prolly struck down somewhere years ago;!!

Quite simple, there was a lower resistance path towards the tree what was closer then the steeple to the discharge point or path rather from the cloud . Sometimes even church steeples are struck from the aide and lower down!

W J Furse of Nottingham now part of the ABB group had an excellent booklet detailing that sort of thing they also have such as analysis programmes as "Strikerisk" to calculate the degree of protection needed.

Have a Google for "Rolling sphere" that will help explain what happened there!..

Thanks.

Not quite brown trousers moment, but by thunder :) it was loud !!!!

IIRC there was a New Scientist in the 1980s (?) that had a spectacular photo that had taken *years* to capture. It was the Eiffel Tower in a lightning storm. The photographer caught a clear *upwards* bolt of lightning meeting the downstrike.

The article mentioned that it had been put forward as a theory, but never proved, until that picture.

Following Rupert Sheldrakes memetic theory of events, there's probably zillions of such photos now. But it was much more than split second.

The earth has an electric field above it, even on a dry clear day.

By flying a kite with a conducting string on it, you can get sufficient energy from this, to run an electrostatic motor.

Such motors were detailed in a book at my public library. The motors looked like a squirrel cage rotor.

It's not clear how stupid you'd have to be, to be flying such a kite setup. If you could visualize the field strength, it might be different. Because there is a possibility of a nasty surprise.

Paul

Sheldrake is an interesting guy.

On a potholing trip, we sat at the cave entrance on the hilltop resting after ascending the mountain. After a short while we noticed a dense black cloud coming our way at eye level. It was suggested we drop inside to a ledge 50ft below for protection. While one guy was rigging a 90ft pitch me and another decide to traverse the exposed rift which we did elbows and knees.

incidentally, the water level of the stream below us raised a good 15ft within a few minutes. While we traversed we both remarked on the low level 'strikes' we were feeling coming from the rock faces.

I wonder how it would have felt if we had remained on the surface where we would have been within the cloud space?

...Ray