ideal machine
英[aiˈdiəl məˈʃi:n]美[aɪˈdiəl məˈʃin]
The term ideal machine refers to a hypothetical mechanical system in which energy and power are not lost or dissipated through friction, deformation, wear, or other inefficiencies. Ideal machines have the theoretical maximum performance, and therefore are used as a baseline for evaluating the performance of real machine systems.