Science & TechFact

Counting seconds tells you how far away the storm is.

Sound moves through 20 °C air at about 343 metres per second; light arrives practically instantly. When you see lightning, count the seconds until thunder and divide by three for the distance in kilometres (or by five for miles). Nine seconds means three kilometres. If the gap shrinks from flash to flash, the storm is approaching.

Useful: Under ten seconds, get indoors; lightning strikes kilometres away from where the rain is falling.

Source: en.wikipedia.org

Akustik Alltag Physik Wetter

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