Question

In circuit breakers, besides air or vacuum, what gaseous medium, in which the arc is elongated, is used?

Short answer

The${\mathrm{SF}}_6$ gas is used for the arc elongation.

Step-by-step solution

Define circuit breaker.

The circuit is defined as a switch used to protect the electrical circuit from overcurrent flow and short circuits. The circuit breaker is designed to detect a fault current or over current and bypass the fault current, and once the fault current is cleared, the electrical circuit comes to its normal condition.

Determine gaseous medium that can be used for arc elongated.

The ${\mathrm{SF}}_6$gas can be used for the elongation of the arc. The sulphur hexafluoride can be used to stretch the arc by using the magnetic field. The sulphur hexafluoride has the high tendency to absorb the free electron. The free electron in the gas is captured by the sulphur hexafluoride gas and due to this arc builds enough strength to extinguish the arc.

Therefore, the gas used is${\mathrm{SF}}_6$.