MadSci Network: Physics |
mara, solids are characterised by their ability to resist deformation. they are able to resist deformation because they can develop much larger internal shear stresses than fluids. these internal stresses counteract the deforming force (and provide a basis for the third law). it's nature's way that these resistive forces start developing the instant the deforming force acts. this should answer the "when" part. how much? as much as you apply on the floor, up to a limit,beyond which point the floor would give. i'm still not sure i've answered your question. if you want to know why this kind of response is "programmed" so to say into the floor's behaviour, then you have uncovered a subtlety.the floor does not follow the laws we make. WE discover laws that explain the floor's behaviour. once again, it's nature's way.
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