A question about friction coefficients....

[Andy Salter]

If a body is moving in one constant direction, is it considered stationary with respect to other directions? For example, consider a table. Let the surface of the table be defined by an x-y Cartesian plane. If the body is moving in the x direction on the table, and a force (< (μ_s * F_n)) is imposed in the positive y direction, does the friction acting in the negative y direction act through kinetic or static friction?

 

[scottdave]

Perhaps this may help, a little. http://ffden-2.phys.uaf.edu/211_fall2002.web.dir/ben_townsend/StaticandKineticFriction.htm
When it is sitting still, the tiny bumps are sort of locked together, but if it is moving past the bumps, even if in one direction, they are no longer locked. So the type of friction is the same in all directions. I kind of simplified it, but I hope it helps.