Velocity ratio in a lifting machine is defined as what?

The velocity ratio in a lifting machine is defined as the distance moved by the effort divided by the distance moved by the load. This definition is crucial because it illustrates how mechanical advantages are achieved in various machines.

When an effort is applied over a certain distance, that distance and the corresponding distance moved by the load provide insight into the efficiency and effectiveness of the machine. A higher velocity ratio indicates that a smaller effort can move a larger load when the distances moved are considered. This relationship is essential for understanding how machines like pulleys, levers, and other lifting mechanisms work to assist in lifting heavy objects with less manual effort.

The other choices touch upon related concepts, but they do not define the velocity ratio directly. The load to the effort ratio pertains to the mechanical advantage rather than the specific relationship of distances moved. The work output to work input ratio refers to efficiency rather than velocity ratio. A block and tackle system is a particular arrangement of pulleys and does not define the velocity ratio itself but is an application where this ratio can be observed.