At this point in your lives, you all know that there are a great amount of bridges around Chicago, and both across the country and around the world. They are extremely important in today's world. Don't take just my word for it, though, here's what Sean Dean, a civil engineer and professional bridge designer, has to say about the significance of bridges:
There are a lot of different physics concepts--many you have already learned in class--that go into building a bridge. There is not just one type of bridge, either. Just like designing a house, bridges have their own designs, too. Depending on its length, whether cars or freight trains will pass over it, and if sits above water or land all go into determining which type of bridge will be most efficient. The more efficiently a bridge is made, the better it is.