Healthy bursae create a smooth, almost frictionless functional gliding surface making normal movement painless. An ideal spring is taken to be massless, frictionless, unbreakable, and infinitely stretchable. Tension forces can be modeled using ideal strings that are massless, frictionless, unbreakable, and unstretchable. The lens floats on a bearing surface of liquid mercury which allows near frictionless operation. This symmetry arises only because the flow is completely frictionless. Problems with flying gravel and its frictionless linear eddy current brake came up during testing. Another theoretical machine involves a frictionless environment for motion. Such conversion may be idealized as nearly frictionless, though it occurs relatively quickly. API based E-mandate process is expected to make the process fast, frictionless and paperless. Using Newton's laws of motion, numerous 18th-century mathematicians solved many frictionless (zero-viscosity) flow problems. Cartilage is the connective tissue responsible for frictionless joint movement. Imagine a train that travels through a frictionless railway line along the equator. Consider a truck on frictionless, straight rails. This page focuses mainly on the normal direction, i.e. on frictionless contact mechanics. Asset management supervision or investment acts ensures the frictionless operation of those vehicles.