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      08-21-2008, 01:36 AM   #162
swamp2
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Quote:
Originally Posted by ArtPE View Post
look at it this way:
60-0 downhill or flat, kinetic, 1/2 (88)^2 ~ 3872 (ignore m, it's constant)
potential g delta h, assume a stopping distance of 112 ft at 10% grade (pretty steep)
U ~ 11 x 32 or 353
total energy ~ 353 + 3872 ~4225...so the added energy is only 8.4% of the total...
as I said, it would make negligable difference...
increasing the speed < 5% would be about the same effect...
I was not refering to a specific case. He asked if the work would be greater and it would. We agree the IRL differences on any real hill would be small.

Quote:
Originally Posted by ArtPE View Post
as far as mass of the disc increasing vs distance/work, the only additonal energy would be that stored by the flywheel effect due to gravity (inertia)
W = distance x F, F = braking force which is the same, so any difference (if any) would be negligable...

distance = W/F since force is constant, and the work is only marginally increase, the distance is not greatly increased...
straight out of the Bosch book page 616
Same point here, a small but real effect. "Magically" move non rotating mass to rotating mass and at the same translational speed you have more energy, period, no argument possible. The same effect is why heavier wheels have a small but measurable impact on vehicle performance, acceleration and braking.
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