Bullwhip wave mechanics: What changes?

AI Thread Summary
As a bullwhip wave propagates toward the tip, the amplitude changes rather than the wavelength. This phenomenon is likened to sound waves in a medium with decreasing density, though the mechanics differ since sound waves are longitudinal. The discussion highlights a divide between proponents of supersonic and non-supersonic whip cracking, with experts disagreeing on the underlying mechanics. A key explanation involves the concentration of kinetic energy into smaller whip segments, which influences the wave's behavior. Overall, understanding the end of the wave's transmission is crucial for grasping the full implications of wave mechanics in this context.
Greylorn
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What wave property changes as a bullwhip wave propagates toward the tip? Wavelength or amplitude?

The problem seemed at first analogous to that of describing the behavior of a sound wave propagating through air of linearly decreasing density, except that sound is longitudinal.
 
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This might help you think about it :)

http://paws.kettering.edu/~drussell/Demos/reflect/reflect.html
 
This is one of those controversial issues that seesaws between rival camps: in this case the supersonic versus the non-supersonic factions. Even skilled whip crackers disagree. The best explanation I've found so far is here: http://home.comcast.net/~a-mcnibble/Rants/WhyWhipsCrack.pdf according to which it's the concentration of kinetic energy into a smaller and smaller whip segment that does it.
 
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univox360 said:
This might help you think about it :)

http://paws.kettering.edu/~drussell/Demos/reflect/reflect.html

Thank you! The link answered the question in favor of amplitude, and is a fine exposition of other aspects of wave mechanics, providing even more to think about. Greatly appreciated.
 
Bill_K said:
This is one of those controversial issues that seesaws between rival camps: in this case the supersonic versus the non-supersonic factions. Even skilled whip crackers disagree. The best explanation I've found so far is here: http://home.comcast.net/~a-mcnibble/Rants/WhyWhipsCrack.pdf according to which it's the concentration of kinetic energy into a smaller and smaller whip segment that does it.

Bill,
Great link! Although I was more interested in the mechanics of a transverse wave in a variable medium (looking for cosmological implications) than in what happens at the end of a wave's transmission, I was being short sighted. The end may be the most important part of the problem. Thank you for the insight!
 
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