it is simple to demonstrate the principle that if a shelving unit you buy at home dept says each shelf can support 50lbs maximimum and you put 49lbs on it plus drop 10 , it will break. and that 59 lbs will drop on the next shelf (holding 10lbs) so now that shelf is experiencing 69lbs so it will break and land on the shelf below it. and so on and so on. the weight each consecutive lower shelf gets hit with is progressively larger ie. unstoppable.This is precisely why it seems like it would be easy to build a simple structure that demonstrates these principles with loads in the 1-3 pound range.