Does lightening cause a form of cavitation?

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Lightning does not cause cavitation in air in the traditional sense, as cavitation typically requires a liquid to form bubbles. Instead, lightning rapidly heats the air to plasma temperatures, resulting in a quick expansion and subsequent cooling that generates a shock wave, heard as thunder. The process involves a rapid increase in pressure and expansion of gas molecules, which differs from the bubble formation seen in fluid cavitation. While there are similarities in rapid expansion and collapse, the mechanisms and environments are distinct. Understanding these differences clarifies the nature of thunder and the effects of lightning on the atmosphere.
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Does lightning cause cavitation of air much like in a normal fluid?

It moves through the air so fast it has the same effect and then we hear thunder as a result?
 
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Cavitation is the creation of bubbles that release energy when they pop. I don't think just air can form bubbles by itself, it would need a liquid to contain it. The lightning is ionizing the air and heating it to a plasma. I don't know if there are such thing as plasma bubbles and so I don't know the answer to your question.
 
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Dragon is correct, that this cannot be cavitation the way we normally understand the term. But it is something similar. With such rapid heating of the air, you have very rapid expansion. That is followed by very rapid cooling and a collapse of the air back to something close to its original volume. This is what makes the noise.

In cavitation, you have a rapid expansion of a gas bubble, followed very quickly by its collapse. Similar, but different.
 
From Wikipedia:
"Because the electrostatic discharge of terrestrial lightning superheats the air to plasma temperatures along the length of the discharge channel in a short duration, kinetic theory dictates gaseous molecules undergo a rapid increase in pressure and thus expand outward from the lightning creating a shock wave audible as thunder. Since the sound waves propagate, not from a single point source, but along the length of the lightning's path, the sound origin's varying distances from the observer can generate a rolling or rumbling effect."
http://en.wikipedia.org/wiki/Lightning

Cavitation in fluids is quite different from lightning. You may Google it to learn more.
 
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