I've been on holiday :) and out of touch with phys-l so maybe someone has
mentioned this...
While waiting for my car to be repaired in Switzerland, between climbing
mountains, I was forced to read Time magazine of 9 August. On p14 there is
a GREAT photograph (better than the one cited on this list on a website
sometime in the past year) of a jet fighter ringed by a cone of vapour
produced by the pressure drop (?) in the shockwave as it flies faster than
sound.
I quote the caption:
" Pressure created by sound waves from the American Navy FA/18 Hornet as it
approaches the speed of sound causes moisture rising from the ocean to
condense into a ball of vapour around the nose of the plane. As the
aircraft travels ever faster and finally breaks the sound barrier, the
cloud is pierced, and blossoms into a diaphanous disk. The rarely seen
phenomenon is caught by a US Navy photographer positioned on a nearby ship."
This caption seems somehow accurate in a descriptive sense and yet totally
obscures the physical explanation of the phenomenon. Challenge: rewrite the
caption so that it's still suitable for Time, and conveys a better idea of
what's going on.
Mark
Mark Sylvester
United World College of the Adriatic
34013 Duino TS
Italy.
msylvest@spin.it
tel: +39 040 3739 255