Any fall of that great of a distance can harm a hamster, but most of the time hamsters are pretty tough little things. My sister's hamster got dropped about 6 feet when he was young, and he was fine. If you start to notice the hamster acting strangely (loss of appetite, squeaking noises, lethargy, milky eyes, wet tail, unusual aggressive behavior, etc), it's probably because something is wrong with it.
