Students could look at the rapid changes to society that the invention of the internal combustion engine led to. The most obvious intervention was the car. How did the car change the lives of those who could afford one? How did Henry Ford's new manufacturing methods improve the speed of assembly and reduce the cost of production?
Arc Flash is the result of a rapid release of energy due to an arcing fault between a phase bus bar and another phase bus bar, neutral or a ground. During an arc fault the air is the conductor. Arc faults are generally limited to systems where the bus voltage is in excess of 120 volts.
WHAT IS ARC FLASH. An Arc Flash is very simply, an electrical short circuit through air. Whether it occurs from phase to ground or phase to phase doesn't matter. What does matter is that enough energy is present to perpetuate the arc. Lightning is an example of arc flash as is an electric arc welding machine. The difference between them is that lightning discharges itself in a very short period of time whereas an arc welding machine sustains the arc indefinitely. Either way, you don't want to get too near either of them.