The energy required to break an object will be independent of the speed of the thing hitting it. This is known as the toughness of a material. That energy is what the striking object will need to impart and this will have the same impact energy imparted to itself. The way this is used in practice on the roadways is by having wooden posts at the end of ...
These scenarios are too simplified to be able to form an opinion.
But generally "unyielding barrier" will cause more damage.
Let's say the yielding barrier never breaks, only bends and moves one meter.
assume these factors just for the sake of a perspective.
car mass M kg
Car speed at crash V
d, distance car moves to a full stop 2 meters for 1st ...
For simplicity, let's hold the speed constant, the rigidity of the walls variable. The sketch below conceptually depicts two scenarios - the car runs into a non-yielding (rigid) wall and then runs into a defective yielding wall.
Car A suffers damage due to the full impact force. The impact of car B will be absorbed partially by the crushed wall, which ...
You should consider sheer density. When the stress increases, the velocity gradient increase.
If the distance between velocity contour lines of say 0,1 m/s difference in speed used to be 1mm originally it becomes roughly 0.09 mm at a stress level of 1.1 times the original stress level.
This doesn't concern the behavior of the liquid at the molecular level.
The way I understand it, is that (at least in laminar flow) viscosity is proportional to the "stickiness" between the layers of the fluid. I.e. higher viscosity, means that if a layer starts to move, then it will sweep along more forcefully the adjacent layers.
Additionally in the example of the Couette flow, the velocity of the top layer ...