Which model in manual handling involves the use of a rigid beam to lift or move loads?

The model that involves the use of a rigid beam to lift or move loads is referred to as levers. In manual handling, levers are an essential principle that describes how a rigid beam (the lever arm) can be utilized to lift or shift heavy objects with greater ease. The basic mechanics involve applying force at one point on the lever, which in turn multiplies this force at another point, allowing for the movement of loads with less effort.

This principle can be observed in many everyday tools, such as crowbars or seesaws, where a small force applied at one end results in a larger force being exerted at the other end. The advantage of using levers in manual handling is that it minimizes the risk of injury by reducing the amount of force required to lift or move an object, promoting safer handling practices.

In contrast, the other options do not specifically relate to the use of a rigid beam for lifting or moving loads. Principles of leverage generally refer to a broader concept of how forces are distributed rather than the mechanics of lifting; gravity wells pertain to gravitational influences rather than manual handling techniques; and support vectors relate to a concept in machine learning and are not applicable in the context of manual handling processes.