Re: Interference pattern & jets

[Tony Wayne <wayne@PEN.K12.VA.US>]

Each band is a speed of sound barrier. The rings you see are called
"mach rings." The ring farthest away from the exhaust is "mach 1." The
net closer ring to the exhaust is "mach 2." etc.

ACSII Art...
                      mach rings
                            |
                            |
                            |
=======+                   \_/
*JET***| )  )  )   )   )    )      )
=======+
         |  |  |   |   |    |      |
         |  |  |   |   |    |      |
Mach #=> 7  6  5   4   3    2      1

-tony

Mike Wilson wrote:
> <From: mwilson@colosys.net>
>
> In watching the military jets take of on the nightly news I notice the
> exhaust exhibits patterns of bright exhaust, dark lines, bright exhaust,
> etc.
>
> Am I seeing some type of interfernce pattern from light?
> Am I seeing some type of combustion pattern (I can't imagine what)?
> Why do I only notice it in military jets?
> Does it depend on the use of after burners?
>
> Best Wishes,
>
> Mike Wilson
> mwilson@colosys.net
> Math/Science
> West Grand HS
> Kremmling, Colorado

--
========================================================
Tony Wayne                  Those that can, do.
wayne@pen.k12.va.us         Those that understand, teach.