Hauling, Rod-loading.
rb608 wrote:
On Nov 10, 2:22 pm, rb608 wrote:
It's my contention, however, the the force terms should be grouped,
and that the unbalanced force causing the line acceleration is
actually (Frt - Flt). This allows your model to fit into the F=ma
equation as:
(Frt - Flt) = Fi * Fa
Having said this however, I'd clarify that in reality, the line
tension Flt and the force on the rod tip (parallel to the line) Frt
are the same force (in opposite directions), because it's the rod tip
that imparts that force to the line. One needs to examine exactly
where one wishes to consider the free-body diagram. Because we're
looking at how the line accelerates, we can leave the rod out of the
equation altogether. The unbalanced force imparted as line tension by
the rod tip F will cause the mass of the line m to accelerate at a
rate a. Because m is constant, more F causes faster a. It's not a
static model because a0. It's a lot simpler mathematically than it
is with a rod in your hands (well, my hands anyway.)
What I basically want to do is to find out the proportions and relations
of line tension to rod loading for any given rod and any given mass of
line. One is of course obliged to assume an optimum cast as well, as
without the correct and constant, ( or steadily increasing) line
tension, acceleration is erratic, and losing tension at any point in the
cast causes it to fail, ( or be less than optimal).
Given that the basic theory is correct, then I only need to graph the
math and I should be able to plug in any data I want and achieve the
optimum by modeling.
Unfortunately, I seem to be having more trouble with the math modeling
than I should be.
It would seem obvious that the force required to tension the line is not
used to accelerate it.
Therefore, the force Lt = the force Rt minus the force Fa. Using the
actual data one can work out the rod loading for any given mass, line
tension etc, for any mass of line within the rod capabilities, among
other things. Thatīs really the point of the exercise, and also to
explain why and how a haul works.
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