How fast were dinosaurs?

When you say how fast dinosaurs were it depends on which dinosaur you're talking about. Just like, you know, mammals today go all the way from you know something like an armadillo or a sloth which, you know, we can outrun on a bad day to animals like cheetahs which can run in excess of a hundred kilometers an hour. Some of the most complete studies have been based on biomechanical models which people can actually construct models of these things using engineering programs and then run them in computers. And it's a lot of work to do this, so there haven't been a lot of animals which have been done, one animal which has been done is Tyrannosaurus Rex, and people have been able calculate from it that Tyrannosaurus Rex could run at a top speed of about eighteen miles an hour.