PURPOSE: To show a type of electrical discharge.
DESCRIPTION: The Jacob's ladder is positioned on top of the Tesla coil as seen in the photograph. The spark starts at the bottom of the ladder, where the small spacing encourages electrical breakdown. The discharge heats the air, which begins to rise. Because the discharge is a region of least electrical resistance, the spark continues along that path, which continues to rise. At the top of the ladder the discharge path rises until it becomes so long that its resistance is greater than the resistance of the shorter path at the bottom of the ladder. At that point the discharge ceases and starts again from the bottom.
REFERENCES: (PIRA 5D40.10)
EQUIPMENT: Jacob's ladder on Tesla coil.
SETUP TIME: None.
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