Cartoon physics

Cartoon physics is a jocular system of laws of physics that supersedes the normal laws, used in animation for humorous effect. Normal physical laws are referential (i.e., objective, invariant), but cartoon physics are preferential (i.e., subjective, varying).

Many of the most famous American animated films, particularly those from Warner Bros. and Metro-Goldwyn-Mayer studios, unconsciously developed a relatively consistent set of such "laws" which have become de rigueur in comic animation. In one common cartoon scenario example, when a cartoon character runs off a cliff, gravity has no effect until the character notices and reacts.

In words attributed to Art Babbitt, an animator with the Walt Disney Studios: "Animation follows the laws of physics—unless it is funnier otherwise."

Specific reference to cartoon physics extends back at least to June 1980, when an article "O'Donnell's Laws of Cartoon Motion" appeared in Esquire. A version printed in V.18 No. 7 p. 12, 1994 by the Institute of Electrical and Electronics Engineers in its journal helped spread the word among the technical crowd, which has expanded and refined the idea. These laws are outlined on dozens of websites.

O'Donnell's examples include:

The idea that cartoons behave differently from the real world, but not randomly, is virtually as old as animation. Walt Disney, for example, spoke of the plausible impossible in 1956.

Warner Brothers Looney Tunes had numerous examples of their own cartoon physics (such as in the Wile E. Coyote and The Road Runner cartoons) or even acknowledged they ignore real world physics. In High Diving Hare (1948), Yosemite Sam cuts through a high diving board Bugs Bunny is standing on, the ladder and platform that Sam is on falls, leaving the cut plank suspended in mid-air. Bugs turns to the camera and cracks: "I know this defies the law of gravity, but, you see, I never 'studied' law!"

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