The Jacob’s Ladder

Sparks > The Jacob’s Ladder

A Jacob’s Ladder is a special arc device with a "V"-shaped Electrode arrangement, which is formed by two Rods. The gap is smallest at the bottom and becomes larger towards the top end of the "V", Figure 1.

Figure 1: Basic structure of Jacob’s ladder

Air by nature is an Insulator. For it to become a Conductor, it must experience Dielectric Breakdown. This occurs if a voltage of 30,000V per centimeter is applied to the air. The air is then Ionized. In a Jacobs Ladder, Dielectric breakdown occurs when a voltage of 30,000 V is supplied to the bottom of the Rods.

An Electric Arc is formed between the Rods and rises along with the hot air. As the arc length increases, its power consumption increases and there is insufficient Voltage to maintain the Electric Arc. The arc extinguishes and the cycle repeats with a new arc forming at the bottom of the rods.

Lightning is the process of Dielectric Breakdown in nature. When the Clouds and the Earth Surface accumulate enough opposite charges, the extremely high Potential Difference between them causes air to be Ionized and conduct Electric Current, the process gives out a huge spark as Lightning, Figure 2.

Figure 2: Principle of Lightning

Sparks > The Jacob’s Ladder