What is the relay or solenoid component that physically moves a mechanically operated device?

What is the relay or solenoid component that physically moves a mechanically operated device?

• A. Armature
• B. Contacts
• C. Coil
• D. Plunger

Answer: (D)

When a relay or solenoid is energized, the coil creates a magnetic field that pulls a movable core. This core is the element that actually drives the mechanism—pushing or pulling to operate switches or linkages. That moving piece is called the plunger. The coil itself is just the magnet that makes the motion possible, not the moving part. The term armature can refer to a moving part in some relays, but in the context of a solenoid-driven actuation, the component that physically moves to actuate the device is the plunger. The contacts stay in place unless the plunger moves them to change the circuit.

When a relay or solenoid is energized, the coil creates a magnetic field that pulls a movable core. This core is the element that actually drives the mechanism—pushing or pulling to operate switches or linkages. That moving piece is called the plunger. The coil itself is just the magnet that makes the motion possible, not the moving part. The term armature can refer to a moving part in some relays, but in the context of a solenoid-driven actuation, the component that physically moves to actuate the device is the plunger. The contacts stay in place unless the plunger moves them to change the circuit.