You know them- they are used to block off construction areas and have the fun reflector strips.
In almost any action movie with a chase scene, cars go rushing through them in a crash of water. I have always thought the water was to keep the things from falling over or blowing away or whatever.
But I still wonder- how much water are they filled with?
Are different ones filled with different things?
Would the contents of these things change the crashing-through ability of them?
Can you crash through them that easily, anyway?