1. Hey everyone! I am currently studying for my final exam and I am trying to review work to start out. When I was reading, it gave me an example of where a person is holding a text book and the person moves the textbook in the horizontal direction. Under the picture they gave an explanation which says: No work is done on a textbook when carried in the horizontal direction at a constant velocity. 2. None 3. Considering Work depends on displacement, I just thought that if you move a textbook up or down and that is displacement, then why can't there be displacement if you move the textbook (or anything) horizontally?