Page 39 - Physics_Form_2

Static electricity

The electrical current and heat generated by
lightning can lead to significant damage to
both property and lives. Lightning can reach A lightning conductor,
temperatures of approximately 27,000 degrees also known as a lightning
Celsius. When lightning strikes, it creates a tunnel- rod, is a metal rod, typically
like gap in the air known as a channel. Once the made of copper, installed
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lightning disappears, this channel collapses, and atop a structure to protect it
the resulting sound from this collapse is what we from lightning strikes.
hear as thunder.

Lightning protection It offers a low-resistance
Lightning cannot be prevented, but protection path for the electrical current
against destruction is possible by using lightning of a lightning strike to
conductors. A lightning conductor works because travel safely to the ground,
the charge concentrates more on sharp points, such thereby preventing damage
as mountains, trees, and tall houses. These sharp to the building. This system
points have a high density of earth charges, so they usually comprises a copper
are liable to be struck by lightning.
wire connecting the rod to a
grounding system, such as a
Structure of the lightning conductor
The lightning conductor in Figure 1.46 is made of: a deep underground copper earth
copper plate, a copper rod and copper spikes. pole. The lightning conductor
should be taller than the
house to be protected. When
lightning strikes the conductor,
electric charges flow along the
wire and are dissipated to the
ground, where they cause no
harm and thereby protect the
building.

Task 1.4

Examine Figure 1.47,
then summarise your
observations. Discuss with
your colleagues for more
understanding.
Figure 1.46: Lightning conductor

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Physics Form 2 Final.indd 33 25/10/2025 10:25