Re: More weight, faster descents??

unforgiven99@xxxxxxxx wrote:
On Sep 30, 4:28 pm, Lou Holtman <lholremovet...@xxxxxxxxx> wrote:
DaveH wrote:
I've seen this notion in various forums. It typically takes the form
of "A heavier bike may be more work uphill, but is faster downhill due
to gravity..." Something like that.
The notion -- which I think is incorrect -- really should take the
form of "Greater total mass (rider + bike + stuff) may be more work
uphill, but is faster downhill..."
In any case, reviewing the elementary physics, doesn't mass cancel in
the equations? Same reason a rock and feather both accelerate at g in
a vacuum? Ergo, that heavier bike isn't getting you down the hill any
faster.
Dave
Yes it is. More weight, equal frontal area (= air resistance).

Lou
--
Posted by news://news.nb.nu (http://www.nb.nu)

The only problem is that work done to overcome air resistance goes up
by the square of velocity while the work done/input to the system by
the mass going up and down the hill is linear with velocity. For any
significant grade, more mass will never speed you up on the descent as
much as it slowed you down on the climb.



True.

Lou
--
Posted by news://news.nb.nu (http://www.nb.nu)
.

Relevant Pages

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