Thunder
When lightning is generated, the electric discharge produces a great quantity of heat that ionizes the surrounding air, transforming it into a plasma (gas consisting of only electrons and nuclei) at an extremely high temperature (10-15,000° C). The air all around expands violently, in a few millionths of a second, provoking the propagation of a compression wave though the air, which we hear as an acoustic wave that produces thunder. Thunder propagates at the speed of sound (350 m/s), while lightning travels at the speed of light (300,000 km/s), therefore the sound produced by the lightning is heard with a slight delay. We can enjoy calculating the distance of a storm cloud by measuring the time-interval from when we see the lightning to when we hear the thunder. With a rather approximate calculation, dividing the number of seconds that have passed by three, we obtain the distance in kilometres.
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Man has always been afraid of lightning, in fact in the past lightning was considered a sign of the anger…
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29 April 2020
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Man has always been afraid of lightning, in fact in the past lightning was considered a sign of the anger…
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The coral reef is one of the ecosystems with the richest biodiversity...
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On Saturday afternoon in Glasgow, representatives of more than 200 countries attending the COP26 United Nations climate change conference reached…
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Man has always been afraid of lightning, in fact in the past lightning was considered a sign of the anger…
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