How can an electric arc be produced?

Answer 1

As a safety disclaimer, parental guidance should be sought by minors before initiatiating any kind of electric arc or using electricity or electrical devices. It is also advisable for everyone to use safety eyewear, such as goggles, before using electricity in the manners described, below and elsewhere, and to avoid areas which contain flammable liquids or gases.

One method of making an electric arc is to connect wires to each side of a low-voltage electric battery - - such as a standard, 1.5 volt, household, battery (i.e., AA, AAA, C, D, etc) - - then touch the unconnected ends together (best seen in a darkened area).

Another method is to use a Tesla coil (created by Nikolai Tesla), which creates long arcs, which have been referred to as "artificial lightning", at least in appearance. Tesla coils are used in school science labs and in science museums. Plasma bulbs produce the same effect, though to a far lesser degree than a Tesla coil, and are available in some retail stores.

Another method is to walk on a fabric carpet, and then touch a metal object, such as a stair rail or oven door. This is a form of "static" electricity, and is the most common way most people produce electric arcs, though, usually, not on purpose. Again, a darkened area makes for the best viewing.

Another View: (Different contributor)

An electrical arc can be created under many circumstances and by several methods. An arc is most commonly created when the potential difference (Voltage) is increased to the point that air has the ability to conduct electricity. Typically this is only possible when the voltage exceeds the KV range (>1000 Volts). And is extremely dangerous depending on the amount of current available supplying the voltage.

An electrical arc is also created when a flowing current is interrupted (A light switch or contactor opening). In this event, the arc will allow the flow of electrons through free air only until the distance between the two contact points prevents the free air to conduct electricity. The effect or duration of the arc can be increased by the creation of Ozone gas that is generated from the heat of the electricity heating the air. The presence of more current will increase the amount of heat, and also the amount of Ozone, so the arc will be larger.

In common practice, the use of a high voltage furnace ignitor, neon sign transformer, and Tesla Coil (All conisdered Transformers) can by used to generate high voltages (More than 5Kv or 5000 volts). Only people with training/experience with high voltages should ever attempt to generate electrical arcs, and with close supervision and safety protocols.

Another source of artificially generating an electrical arc is the use of a Van De Graff Generator. Where a mechanical source is used to turn a non-conductive belt to deposit electrons on a stationary screen. Thus the arc is created by 'static electricity' (The same effect as rubbing your feet across a carpet, then touching a door handle) The electrons accumulate until a sufficient charge is built up to allow for discharge across free air to a ground reference. Typical charges are in excess of 10Kv (10,000 volts) and while they are low current, should still be considered dangerous.

Modern 'Stun Guns' use a principle of combined capacitance & artificial frequency generation to turn relatively low DC (Direct Current) voltages into high frequency, high voltage (albeit low current) electrical arcs...