The phrase refers to the action of lengthening a “jack,” which is a mechanical device used to lift heavy objects. The extension of this device allows for increased vertical displacement of the load it supports. For instance, if a vehicle requires significant clearance for maintenance, the mechanic might extend the jack to its full range, ensuring safe and unobstructed access to the undercarriage.
This ability to increase vertical height is vital in numerous fields. It enables repairs on vehicles, stabilization of structures during construction, and the lifting of heavy machinery for relocation or service. Historically, basic jacks were employed using leverage principles, but modern designs incorporate hydraulic or pneumatic systems, augmenting the reach and lifting power.