Think of everything in the world as objects with springiness , nothing is "absolutely rigid" , rigid objects in Newtonian mechanics are really really tight spri

Think of everything in the world as objects with springiness , nothing is "absolutely rigid" , rigid objects in Newtonian mechanics are really really tight springs that deform very little to push back with a huge force. So a "rigid" block on a "rigid" table is really two springy objects that deform to equilibrium i.e when the normal force exactly equals the weight of the block