Lightning is a sudden
electrostatic discharge that occurs typically during a thunderstorm. This
discharge occurs between electrically charged regions of a cloud (called
intra-cloud lightning or IC), between two clouds (CC lightning/Cloud-Cloud
lightning), or between a cloud and the ground (CG lightning/Cloud-Ground
lightning).
Lightning is one of the most
destructive forces in nature. But for all the folklore and legends amassed over
human history on lightning, we know surprisingly little about the inner workings
of this powerful phenomenon, including something as simple as how the current
that flows through a thunder-inducing flash is related to the temperature of
the strike.
The charged regions in the
atmosphere temporarily equalize themselves through this discharge referred to
as a flash. A lightning flash can also be a strike if it involves an object on
the ground. Lightning creates light in the form of black body radiation from
the very hot plasma created by the electron flow, and sound in the form of
thunder. Lightning may be seen and not heard when it occurs at a distance too
great for the sound to carry as far as the light from the strike or flash.
There are approximately 100,000
lightning strikes on Earth every single day, the randomness of the occurrences
makes it difficult for scientists to study them in an effective or systematic
way. But scientists use special device for generating artificial lightning,
such device or system is known as an impulse current generator system, the
device can create artificial lightning with currents up to tens of thousands of
amperes. For perspective, a household or automotive fuse is usually rated well
below a hundred amperes, and an electric current of just a few amperes can
easily kill you.
During a storm, colliding
particles of rain, ice, or snow inside storm clouds increase the imbalance
between storm clouds and the ground, and often negatively charge the lower
reaches of storm clouds. Objects on the ground, like steeples, trees, and the
Earth itself, become positively charge creating an imbalance that nature seeks
to remedy by passing current between the two charges.
Many houses are grounded by rods
and other protection that conduct a lightning bolt's electricity harmlessly to
the ground. Homes may also be inadvertently grounded by plumbing, gutters, or
other materials. Grounded buildings offer protection, but occupants who touch
running water or use a landline phone may be shocked by conducted electricity.
LIGHTNING STRIKE TEMPERATURE
Lightning is the movement of
electrical charges and doesn't have a temperature; however, resistance to the
movement of these electrical charges causes the materials that the lightning is
passing through to heat up.
Lightning is extremely hot, a
flash can heat the air around it to temperatures five times hotter than the sun’s surface. This heat causes
surrounding air to rapidly expand and vibrate, which creates the pealing
thunder we hear a short time after seeing a lightning flash.
If an object is a good conductor
of electricity, it won't heat up as much as a poor conductor. Air is a very
poor conductor of electricity and gets extremely hot when lightning passes
through it. In fact, lightning can heat the air it passes through to 50,000
degrees Fahrenheit or 27,760°C
(5 times hotter than the surface of the sun), The temperature of the sun’s surface is about 10,000
degrees of Fahrenheit or 5538°C.
Lightning's extreme heat will
vaporize the water inside a tree, when lightning strikes a tree, the heat
vaporizes any water in its path possibly causing the tree to explode or a strip
of bark to be blown off or may blow the tree apart. Cars are havens from
lightning, but not for the reason that most believe. Tires conduct current, as
do metal frames that carry a charge harmlessly to the ground.
Posted by: Lusubilo A. Mwaijengo
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