🚀 go-pugleaf

Mike Sweeney <msweeney@nospam.lr.net> wrote:
>Marc wrote:
>> joelga@pebble.org (Joel Garry) wrote:
>> >On Mon, 06 Jul 1998 00:12:25 GMT, E. Faubion <in@the.sig> wrote:
>> >>"Mark B." <spam_*this*_@see.my.sig> wrote:

>> >>>Earl, face the facts -- your one-size-fits-all c.o.f. model is
>> >>>*PURE BULLSHIT*.

>> >>You really don't understand the problem do you?  The c.o.f. is a
>> >>variable determined from testing based on the vehicle and surface in

>> >You don't really know what variables and coefficients are, do you?

>> I think that he may actually know what he is doing, but that he isn't
>> able to convey the ideas in his head.

>> The simple fact of the matter is that a coefficient is a constant in
>> an equation (not a variable), but that it can change (it is variable).

>> His statement is incorrect, since CoF is most definately *not* a
>> variable in any equation he uses.

>> He's afraid to start speaking with the correct terminology because,
>> like most crusty old people, he doesn't know the proper way to say
>> what he is thinking, even if he actually did know.

>> He's too much of a coward to somply state what he believes, and likes
>> to condescend to others, even if that makes his statements incorrect.

>> Marc
>> For email, remove second "y" from Gumbyy@ticnet.com

>At least he isn't so immature that he addresses whining comments about
>specific people to other people.

He's already put me in a killfile for asking him tought questions, so
I will insult him every chance I get.  He did the same with me for a
long while.

>Coefficient of friction is the ratio of the force necessary to slide an
>object at uniform speed on a particular surface to the pressure of the
>object against that surface.  --Traffic Accident Investigators Manual for
>Police, Northwestern University Traffic Institute.
>
>Drag Factor -- the amount of drag that a surface puts on a tire(tires) on
>a wheel compared to the weight on that wheel.
>
>The drag factor with sliding wheels is the average CoF during the slide,
>because (definition:above.)
>
>Drag factor may also be used to represent the drag on the road by wheels
>which are rotating but with the brakes applied to little to lock them.
>
>ABS lets the brakes lock, then immediately releases them for a fraction of
>a second, then begins to lock them again.  For this reason, most ABS
>vehicles, under pedal-to-the-floor braking can be heard to squeal almost
>as loud as regular vehicles, and will often leave light skidmarks.  Since
>this is possible, the difference between that and a vehicle without ABS is
>less than you might think.

The Saturn I engaged the ABS on while on dry pavement left
intermittent skid marks.  They were about 4 in. long with about 4 in.
of space between them.

>Also you would have to understand that large variances in skid resistance
>(drag factor) are equal to much smaller variances in speed.
>
>Beginning to understand why this is usually doled out in a series of
>classes?  (all of which EF has probably taken)
>
>I am.  All the information above is in all the books I could locate on the
>subject with minor wording differences.

None of that is anything that I haven't heard before.  I've not had a
class in accident reconstruction, but it doesn't seem to cover any
math or physics that I haven't already had in my multiple physics,
calculus, and engineering classes.

Having covered subjects such as aerodynamic drag, I can't see how
calculating the drag of four little patches of rubber (well, not true
rubber anymore, but still the same idea) compares to the drag of air
on an airplane.

In your post above, did you say anything contrary to my statement that
CoF is variable but not a variable, despite Earl's statements to the
contrary?  Do you agree with Earl's statement that "The c.o.f. is a
variable..."?

Marc
For email, remove second "y" from Gumbyy@ticnet.com