You better learn to read. From your own source "(typically hundreds to
thousands of kV and 10-100 kA) " energy that does not get bled off allows
lots of energy to attack your tree or house. Not every lighting strike
causes damage, but enough do. You use joules, same as BTU, watt-hours,
horsepower, foot-pounds. All an energy source. As sto nails, even a
common 16p construction nil can be forced partially in to a wood stud by
hand. Enough to hold it in place for a hand held hammer to strike it and
drive it into the wood. In otherwords the hammer as an extension of the
hand / arm does a good job of driving in the nail.
Bill


"w_tom" wrote in message
...
From Colin Baliss "Transmission & Distribution Electrical
Engineering":
Although lightning strikes have impressive voltage and current
values (typically hundreds to thousands of kV and 10-100 kA)
the energy content of the discharge is relatively low and most
of the damage to power plant is caused by 'power follow-through
current'.

Martin A Uman All About Lightning
Most of the energy available to the lightning is converted along
the lightning channel to thunder, heat, light, and radio waves,
leaving only a fraction available at the channel base for
immediate use or storage.

Accurately provided were joules for lightning strike numbers
you had provided - an extremely low energy event. Atom bombs
are completely irrelevant. And a human hand cannot push a
common nail into construction wood. You have even reversed
facts from previously reply. I did not say "lighting has no
power, just lots of energy." Even the 'nail in wood' example
does not demonstrate "no power ... lots of energy". Please
read with more care. Meanwhile people who actually do this
stuff are quoted above.

The OP defines a lightning strike that the author even
witnessed. He demonstrates what is standard in most lightning
strikes and why effective protection is required. He said:
I walked around outside and cannot see any evidence that the
lightning hit the house or even the ground. I thought if it
did it would at least leave a burn mark.

That OP simply repeats what was well proven by the US
Forestry Service.

Bill McKee wrote:
Watts are an power / energy measurement. Just like Joules, dynes,
Horsepower. True that true power would be Watt-hours. But that
50000 watts over a couple of milliseconds can do tremendous damage.
And that damage takes power. It takes only very short pulse from
a very large laser to trigger a hydrogen pellet to begin fusion.
An atom bomb only fissions for an extremely short time, but lots
of power is generated. As well as lots of energy generated. And
a human can push a nail into a block of wood. Small nail, but not
a railroad spike (large nail). Just different amounts of energy
expended. Oh well, I guess my engineering degree is invalid, and
lighting has no power, just lots of energy.