What is a fundamental property of liquids that makes them suitable for hydraulic operations?

The property that makes liquids particularly suitable for hydraulic operations is their incompressibility. In general, liquids occupy a definite volume and do not compress significantly under pressure like gases do. This characteristic allows hydraulic systems to transmit force efficiently and reliably across the system without significant changes in volume. When pressure is applied to a liquid, it uniformly transmits that pressure to all parts of the contained liquid, which is fundamental to the operation of hydraulic brakes, lifts, and other equipment that rely on the transfer of force through liquids.

While viscosity is important for flow characteristics, and elasticity pertains more to solids than liquids, those factors do not fundamentally enable the effective transmission of power in hydraulic systems like incompressibility does. Capillary action, meanwhile, is more relevant for discussing fluid movement in small spaces and does not play a direct role in hydraulic operations. Therefore, incompressibility stands out as the crucial property for effective hydraulic functioning.