text: Particles close to a surface do not move along with a flow when adhesion is stronger than cohesion.
  At the fluid-solid interface, the force of attraction between the fluid particles and solid particles (adhesive forces) is greater than that between the fluid particles (cohesive forces). This force imbalance causes the fluid velocity to be zero adjacent to the solid surface, with the velocity approaching that of the stream as distance from the surface increases.
  The no-slip condition is only defined for viscous flows and where the continuum concept is valid.