Re: does bodyweight affect the speed of a snowboarder

The body weight can affect the speed of a snow boarder.  In general, the
coefficient of friction between the board and the snow is going to be
independent of the weight applied on the board, but there are limits. 
Pretty
good analogy is to consider the effects of weight on a ship.

A very heavy snow boarder will cause the board to press deeper into the
snow,
potentially bringing the edges of the board into contact with the snow. 
This is
may cause a drag force as the edges of the board cut through the snow.
Presumably, the nose of the snow board is turned up (like on a skateboard)
to
prevent plowing into the snow.  The heavier the boarder the lower into the
snow
the nose will ride.  On very loosely packed snow the nose of the board
could
actually be below the snow level for a heavier boarder.  A more exagerrated
example of this is a fully loaded ship versus a lightly loaded ship.  In
the case
of the ship, the drag force between the ship and water is dependent on how
much
of the ship is below the water line.  A fully loaded ship sits lower in the
water and has more drag than a lightly loaded ship.

Another thing to consider is the continuous collision that occur with
irregularities in the hill.  A heavier snow boarder will maintain more
forward
momentum after colliding with a rise in the snow than a lighter snow
boarder.
Againi, let's go back to the ship analogy.  A light vessel gets buffeted by
waves
more severely than a heavier vessel.  The waves reduce the forward speed of
the
ship by continually knocking it off course (i.e. reduced kinetic energy
from
inelastic collisions).

It seems to me that the two effects mentioned above tend to cancel each
other
out.  Probably not exactly, but enough so that the difference in weight of
boarders is going to produce less of an effect on speed than other more
important effects like: best line of descent, board wax, and balance (it is
difficult to go fast when you are swerving or falling all over the place).

In addition to the above, a heavy boarder will be able to change her mass
distribution more drastically which could lead to faster spins and flips. 
But
this is as much a function of height and flexibility as it is mass.

For more information, I recommend reading about friction and drag in a
entry
level physics textbook or maybe a chapter on the physics of ships.

Sincerely,

Tom "Low Rider" Cull