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Re: Do we need ropes?
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Yes, but the problem with extending the fulcrum is that the forces start to get a vertical component in the wrong direction i.e. one that is trying to lift the strut (and the tower). The longer you make the strut, the less of a problem this will be, but from the top of a 24 foot tower you'll need a very long strut. It needs to be 34 feet long just to get 45 degrees and that will give a vertical force equal to the horizontal force. As soon as you start extending the fulcrum in a horizontal direction, you have lost the "levering at 90 deg" principle; all the forces from the fulcrum act horizontal on the strut and will give rise to an equivalent vertical force. To get an angle of 60 degrees from vertical needs struts 48 feet long and still gives a vertical force of 50% of the horizontal. That's 3.5 tons lift on the tower.

If we use the lintel as a counterweight for the pole and rope method then we have a weight of 10 tons. The torque required to rotate the stone is 218 foot-tons, so in theory at least, the pole could be as short as 22 feet.


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Steve Gray
Posted by Steve Gray
17th September 2003ce
18:22

In reply to:

Re: Do we need ropes? (GordonP)

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Re: Do we need ropes? (GordonP)

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