Movie physics – the good and the bad

One of those “How did I get here?” sites I found recently is the Intuitor Insultingly Stupid Movie Physics page. The site covers a lot of the bad physics we see in movies, and then gives a brief review of the quality of the physics displayed in some recent movies. What kind of things are covered on the site? Well:

Flashing Bullets

The terrorist unleashes a lengthy burst of submachine gunfire as the hero runs along a gangway in an industrial plant. Bullets bounce everywhere. This would be a dramatic event for almost anyone, yet moviemakers feel it must be enhanced. The special effects representing impacting bullets give off bright flashes of light. Normal bullets, especially handgun bullets, do not.

. . .

Problems with Windows

No, we’re not referring to Bill Gates’s woes (or lack of them), but to the ways movie windows refuse to obey simple laws of physics. Apparently no one in Hollywood has ever picked up a piece of broken glass and suffered the inevitable bloodied finger.

Saying that shards of broken glass are razor sharp is an understatement. A shattered window contains thousands of incredibly sharp edges and dagger-like points. It takes almost no force for one of these points or edges to cause a laceration. However, people in movies routinely jump through plate glass windows without receiving a single scratch.

All told, there are nearly a dozen descriptions of bad physics in movies, and the reality behind the false portrayals. My favorite, which has a few simple diagrams that show the Hollywood and the reality behind it, is the issue of lasers.

Visible Laserbeams
From security systems to space adventures, conveniently-visible laserbeams are a common part of our movie experience. Too bad they often don’t reflect reality.

Multi-beamed laser security systems are a frequent Hollywood plot device. Again and again movies feature tension-filled scenes in which characters snake their way through mazes of laserbeams artistically arranged in random patterns by professional security fools to entertain us by making would-be thieves do contortions. A simple arrangement of closely-spaced parallel beams would be contortion-proof but certainly not as much fun.

[tags]Physics, Movies[/tags]