Lightning never strikes twice – a turn of phrase often used to reassure someone who’s had a bad experience, implying that it won’t happen to them again. However, as unlikely as it statistically may be that lightning will strike a specific object, the odds are exactly the same for it to strike the same object at some other time; both events being unconnected. This same principle applies to a lottery. The odds of a specific number coming up are always the same, irrespective of whether it has come up before. So, it is just as likely that lightning will strike an object a second time as it was in the first instance.
What is lightning?
In simple terms, lightning is an electrostatic discharge between two atmospheric parts or the atmosphere and the ground. We have lightning within a cloud and cloud-to-ground lightning. This charge imbalance can be the result of the rapid movement of air within a cloud and can exceed 1,000 volts per metre. If you then add moisture to the mixture, the cloud itself, fog or rain, this can facilitate the equalisation of this imbalance. This is lightning.
When lightning occurs, the path it travels along becomes incredibly hot. We have all experienced electrical wires feeling warm or even hot to the touch, because we had plugged too many devices in to the other end. The voltages here are in the hundreds and the current, measured in amperes or amps, and well below 100. The resulting watts (volts times amps) are thus in the low thousands; think of something along the lines of an electric heater.
この記事は Practical Boat Owner の February 2021 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、9,000 以上の雑誌や新聞にアクセスしてください。
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この記事は Practical Boat Owner の February 2021 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、9,000 以上の雑誌や新聞にアクセスしてください。
すでに購読者です? サインイン
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