Where's the difference between a helmet and a helmet?
If it's a helmet:1 if a pebble falls, then the situation is: the helmet has nothing to do and nobody has anything to do.2 if a brick fell, then the situation is: the helmet shell will be broken, no matter. Because the helmet absorbs most of the impact energy through crushing and crushing.
If it's a safety helmet:1 if a pebble falls, then the situation is: the helmet is nothing, and there is nothing wrong with it.2, if a brick falls, then the situation is: the helmet does not matter, people's cervical vertebra will be broken. Because all the shock energy is taken by the human, it is consumed.
While expanding, the coach introduced the difference between the helmet and the helmet we used.
