Mechanical Engineering - Workshop Technology - Discussion

The correct answer is all of these.

In arc welding, the electric arc is produced by a combination of factors:

1. Voltage: The voltage applied between the electrode and the workpiece creates an electric field, which ionizes the air and creates a conductive path for the arc.
2. Flow of current: The flow of electric current through the electrode and the workpiece sustains the arc.
3. Contact resistance: The contact resistance between the electrode and the workpiece generates heat, which helps to initiate and maintain the arc.

When the electrode is brought close to the workpiece, the voltage applied between them creates an electric field. As the electrode touches the workpiece, the contact resistance generates heat, which melts the electrode tip and creates a conductive path for the arc. Once the arc is established, the flow of current sustains it.

All three factors - voltage, flow of current, and contact resistance - are necessary to produce and maintain the electric arc in arc welding.

The answer is flow of current by keeping good distance between electrode and workpiece. No resistance because one positive and other is negative.

Flow of current is the right answer.

The circuit is open with a small distance.

So, there is a contact resistance between electrode & w/p with ionized air. Due to that contact resistance arc is produced. If there is no resistance in contact, then-current flow freely & electric arc will not be produced.

In the resistance welding process, the contact resistance is used.

Whereas in Arc welding process the arc is produced due to high current.

Flow of current is the right answer.

Arc welding is possible only when the circuit is open and voltage is max and current is zero so the answer is A.

If there would be no resistance or very less resistance is provided then there would be no chance of any electric arc propagation in the gap. So answer is resistance not current.

Arc is produced only the electron jump into negative to positive so the answer must be a flow of current. Not contact of resistance there is no contact.

In resistance welding, the heat is produced by high amperage current and as a result resistance heat welds the contact metals, while electric arc welding creates heat using electric current.