[Paddlewise] In-Reply-To: Force x Distance>

Not quite correct.  Force times distance will give you the work performed.
Force times distance divided by time will give you the power required.
However, the energy input to perform the work depends on the efficiency of
the process.  At 100% efficiency they are equal.  At 50% efficiency twice
the energy is required to do the same work.

My experience and arms tell me the paddle does make a difference.  Changing
the direction of a paddle from a straight line requires acceleration.
Starting with the basic equation -  

Force = Mass X Acceleration, 

For a given paddle stroke (equal speeds and stroke shape) hence the same
accelerations, a paddle that weighs half as much will require half the
force to move through that same arc at the same speeds.  If you watch
paddlers you may notice the people using the heavier paddles tend to
compensate by using a more circular stroke than some who use an ultralight
paddle.

At 04:43 PM 7/22/98 +1000, Laurie Ford wrote:

>If the afore mentioned coach is correct, and paddling is like pulling your
>kayak through the water from stake to stake, then you are going to use 'X'
>amount of energy to move yourself and the kayak, say one kilometre. The
>paddle itself must be irrelevant.
>
>If you move a certain weight through a certain distance, laws of physics
>will tell you exactly how much energy is needed. It's irrelevant whether you
>are using a diesel engine, steam power, or man power.
>
                        ,,,
                      (o o)
==================oOO--(_)--OOo==========================
                  Bob Washburn
whiterabbit_at_iw.edwpub.com  or   rwashbu_at_siue.edu
The only difference between a rut and a grave is the depth.
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