JBaumgarte@aol.com wrote:
>
> In a message dated 6/13/01 8:20:39 AM Central Daylight Time, K7LXC@aol.com
> writes:
>
> << You sure? Isn't a hundred-pound load going to weigh 100 pounds no
> matter
> how the block and tackle are set up? The load effort on the end of the rope
> will be reduced but the dead weight of the load stays the same. You still
> need a suitable ginpole.
>
> Cheers, Steve K7LXC >>
>
> Good grief! Steve, as usual, is correct. It matters not whether you have a
> 4:1 or 8:1 block and tackle set up for lifting--the load on the gin-pole is
> the same (actually plus the weight of all that rope).
WRONG! the higher the mechanical advantage of the block and tackle the lower
the load on what is holding it up(diregarding the weight of the tackle itself).
i'm sorry if you just don't get it, i've explained it as many different ways as
i can. maybe you should go see a mechanics professor at a local college or
something and figure out how to balance the forces on the pole.
but what you really have to understand for the basic ham case with only a single
pulley at the top of the gin pole is that the pole has to be able to hold more
than twice the dead load you are lifting.
--
David Robbins K1TTT
e-mail: mailto://k1ttt@berkshire.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://k1ttt.net
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