NEIEP Mechanics Practice Exam

What part of the jack moves to raise and lower the elevator?

1. Head

2. Plunger

3. Cylinder

4. Base

The correct answer is: Plunger

The correct answer is the plunger. In hydraulic systems, such as those used in elevators, the plunger is the component that moves to create the upward or downward motion required to raise or lower the elevator. When fluid is pumped into the cylinder, it causes the plunger to extend, pushing the elevator upwards. Conversely, when fluid is released from the cylinder, the plunger retracts, allowing the elevator to descend. The head typically serves as the top part of the jack or actuator but does not move to raise or lower the elevator. The cylinder is the housing that contains the plunger and the hydraulic fluid but does not itself move; it provides the structure within which the plunger operates. The base is the support structure that stabilizes the jack and does not play a direct role in the movement of the elevator. Understanding the specific functions of each component is crucial for grasping how hydraulic systems operate in raising and lowering mechanisms.