Theoretically predicted adatom diffusion mechanism on the fcc surface of some common metals, including Copper, Aluminum, Silver, Gold, Paladium, Platinum, and Nickel. A single atom makes a knight's move across the surface via the illustrated exchange. The primary atoms are colorized for demonstration purposes. All atoms are of the same element. Credit: J.M. Cohen, Los Alamos Nat. Lab, New Mexico Tech, 4Physics.
Motion of a Spinning Top
There are many forms and shapes of spinning tops, and they are put into motion in an interesting variety of ways. Some are spun by snap-twisting a center stem with your fingers and releasing. Others are spun using a cord. Regardless of how the tops are spun, they behave in a similar fashion.