In a conventional contactor, current flow through the coil creates a _____ to seal in the armature and maintain the contacts in a switched position.

In a conventional contactor, current flow through the coil creates a _____ to seal in the armature and maintain the contacts in a switched position.

• A. Electric Field
• B. Magnetic Field
• C. Mechanical Force
• D. Magnetic Flux

Answer: (B)

When current flows through the coil of a conventional contactor, it creates a magnetic field in the core and gap to the armature. This magnetic field pulls the armature toward the core, generating a mechanical force that closes the contacts and then holds them in the switched position as long as the coil is energized. The field is the active factor here—the magnetic field causes the motion and the holding action. A magnetic flux is a way to describe the strength of that field, but the coil’s effect is the magnetic field itself; an electric field wouldn’t directly move the armature in this device, and a mechanical force is the result of the magnetic field, not the source.

When current flows through the coil of a conventional contactor, it creates a magnetic field in the core and gap to the armature. This magnetic field pulls the armature toward the core, generating a mechanical force that closes the contacts and then holds them in the switched position as long as the coil is energized. The field is the active factor here—the magnetic field causes the motion and the holding action. A magnetic flux is a way to describe the strength of that field, but the coil’s effect is the magnetic field itself; an electric field wouldn’t directly move the armature in this device, and a mechanical force is the result of the magnetic field, not the source.