1.1 What is friction? Take this everyday example: when a coffee mug rests on a flat table, the kinetic frictional force is zero. There is no force trying to move the mug across the table, so there is ...

I'll be honest—friction is pretty complicated. Imagine that I have a block of wood sliding on a table. In some way, the atoms on the surface of the wood block are interacting with the surface atoms on ...

Cold ions sliding across periodic energy-potential patterns formed by lasers have been used to elucidate the physics of dry friction between crystals. Experiments with no more than six ions suffice to ...