Agree, the best explanation so far.

When two objects collide to each other, the so-called "damage" is the result of the elastic 塑性碰撞. On the contrast, 彈性碰撞is not going to cause any damage because by definition "彈性" means the object will bounce back to its original shape. Just like if you throw a rubber ball to the ground, it will bounce back to your hand and it is still the same ball. There is no need to repair the ball. 塑性碰撞 is different. The object will deform permantly after the collision. And if you want the object back to its original shape, a repair is needed. 

If a car is stronger in struture, which means it will withstand higher force before the permanent deformation starts, it is more likely that it will receive less damage in a collision. And it is nothing to do with the mass or weight of the car. But, if the car is heavier, usually it will be stronger than a lighter car.    

 

 

 

你即使明白牛頓第三定律和動量守恒定律也不會知道碰撞結果。

打一個比方，一支箭迎麵射向跑得很快的獵豹。動量小的箭沒有損壞，受傷的是獵豹。碰撞，通常是以強度小的物體的變形吸收大部分能量為結局的；理想彈性體之間的碰撞例外，因為沒有能量損失