The macroscopic length scale is the scale of size at which objects can be observed with the naked eye. It is also sometimes referred to as the "large scale" or "macroscopic scale." On this scale, objects can range from centimeters in size to meters or even kilometers. Examples of items seen on the macroscopic scale include houses, mountains, and even galaxies. At the macroscopic level, physical processes such as wave motion, diffusion, and reaction-diffusion can be observed. It is also the scale at which Newtonian mechanics holds true. That is, objects with masses on the macroscopic level interact with each other in a predictable and consistent way. In contrast to the microscopic scale, where quantum mechanics governs the behavior of particles, the macroscopic scale is dominated by classical physics.