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Lightning

المؤلف:  GEORGE A. HOADLEY

المصدر:  ESSENTIALS OF PHYSICS

الجزء والصفحة:  p-343

2025-11-30

677

This high potential positive charge in the clouds induces a negative charge in the earth beneath, and as soon as the difference of potential between them becomes great enough, the spark, or lightning flash, breaks through the air, taking the path of least resistance, and generally striking a tree or some other high object. It happens sometimes that the negative charge is induced in a neighboring cloud, and then we see a beautiful display of lightning between the two oppositely charged clouds, and no damage is done by the discharge.

During the hot weather of summer there are few nights in which one cannot observe the reflection, from clouds near the horizon or from the air, of flashes of lightning in a distant storm. The storm may be fifty miles away and entirely below the horizon. This form is often erroneously called heat lightning.