Last modified: 17:42 Jan 20, 1999
The "laws of physics" aren't the same in the world of cartoons...
One attempt to quantify them is by trying to write down "laws" like Newton's laws of motion for cartoon worlds. Here's another version, and yet another. And here's an attempt to understant the physics of the Simpson's Itchy and Scratchy.
The main thing about animation is that since the animator is in control of everything, they can make anything happen. The trick is to somehow use the amazing amount of control in service of the story or goal of the animation.
Another element is that there needs to be some "law" to help the audience be able to predict what is going to happen (except, when something unexpected should happen intentionally, to surprise the audience). The Looney Toons Road Runner cartoons are a great example of this.
The "rules" (or physics) of the Road Runner: (taken from Chuck Amouk, by Chuck Jones)
See the Wile E.'s page for more Road Runner fun