Poor Cows
 Fred |
 Lilly |
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OK. Now we know that we can get injured even if the lightning bolt doesn't strike us directly.
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Yes, because we can get an electric shock from the current that flows through the ground. But why
are cows in greater danger than people?
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Good question. I have just found the following information on the internet about lightning bolts:
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Field strength and potential niveaus of lightning bolts
When we talk about a lightning stroke we mean both effects: the direct stroke as such and the damage resulting from the current spreading in the ground in a cone-shaped area.
At the spot where the bolt strikes the ground, a strong electric field is the result.
The field strength decreases from the centre to the outside. In the ground the field strength decreases conically.
Here you can see different sketches of potential niveaus:
Within one potential niveau the voltage is always the same. Because of this such niveaus are called equipotential lines.
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Now I can imagine why a lightning bolt striking close to a cow is still dangerous for the animal. I assume that the potential difference
between the different potential niveaus is the main cause for this!
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Why do you think? Why is the potential difference that bad for the cows?