Sunday, April 09, 2006

"High-speed Imaging of Shock Waves, Explosions and Gunshots":
...[O]ur research group has taken modern high-speed videography equipment and combined it with some classical visualization methods to image shock waves from explosions and gunshots in more realistic environments. This allows us to capture the development and progress of these wave fronts on a scale that has not been possible in the past.

...Hollywood clearly does not understand shock waves, resulting in some ludicrous cinematic special effects. On television, Bart Simpson sent a shock wave rippling across Springfield by yelling into a row of megaphones ganged together in series. Children who try this at home will be disappointed -- it doesn't actually work to produce shock waves. In movies, the hero might outrun the blast from an explosion on his motorcycle. Real motorcycles cannot begin to approach such speeds, and if they did they would not likely stay on the ground. But actual shock waves, in fact, are much more interesting than anything Hollywood has come up with so far to represent them.
The article includes a nice discussion of the physics of shockwaves, as well as links to multiple cool images such as a the bullet penetrating a banana, firing a .44 magnum revolver, firing a .45 pistol without and with a silencer, and a rupturing balloon.

(Via Science News.)