Answer should basically say: “1. Arcing corroded the soft copper switches with pits. Dirt and moisture compounded the problem. 2. As motors became larger, It was physically dangerous to handle the switch.”

A contactor connects or disconnects the motor from the power supply.

Answer should basically say: “A magnetic contactor is operated electromechanically without manual intervention. This means that the contactor can be operated remotely, without the need for putting a person in a potentially dangerous location.”

Answer should basically say: “1. As contacts open and close, an electrical arc is created between them. The arcs produce additional heat, which, if continued, can damage the contact surfaces. 2. Modern contactors close so quickly and with such energy that the contacts slam against each other and rebound, causing a bouncing action. When the contact bounces away, a secondary arc is created.”