Physics: I need a formula for determining the depth of a lure trolled
at a certain speed an X distance behind a boat. Because of fluid
dynamics, there is a maximum depth that a lure can reach at a certain
speed. The more line you let out, the deeper a lure goes, but a
certain point the lure just won't go any deeper. This is called
'blowback'. Knowing angle of water entry, line length, line diameter,
line mass, speed of vessel, lure diameter, height above water, lure
mass, how deep is the lure, and what is it's maximum depth? Assume the
lure is a straight cylinder, and attatched to the line at the forward
tip, dead center. I can provide addition information if required.
Thanks!

To Tackel Such Question you Will need to have a Knolege on the following topics:

Benullie equasion, Flow and Continuity, Specfiic Gravity, Relitive Dencity.



Obviously there are alot of Variables you have mention, i am quite
sure there is not a specfic Formular for this, however im sure an
Expression can be derrived from working out each individual component
seperately.
My Suggestion would be to calculate how deep the lure goes when the
boat is not moving. (to work this out you need the Relitive dencity of
Sea Water, The mass of the lure, and Gravity field strength)   then
you can relate the height of the lure to the speed of the boat.


Make no mistake this is possible to do, it will take alot of allpied
maths to do, however to save me time i would like to know what your
level of understanding is of Fluid Mechanics. (to do somthing like
this is at Univercity Level and a good understaning of applied maths
will be the key)

Please provide the Infomation, and i can work you throught this
problem step by step.


Alex  (Mechanical Engineering undergratuate B-Eng)