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Originally Posted by akoscielski3
First off I never mentioned putting constant force springs on the elevator to eliminate almost all of the weight.
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A loaded spring provides an extra source of power and changes the calculations.
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the 28lbs included the outside rail, which is not being lifted at all
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If the center of mass of a 28-lb assembly changes from 31" to 57" (a difference of 26"), it doesn't matter what parts move and what parts don't: it still takes 28*(26/12) foot-pounds of work. If you lift the whole assembly 26", or if you only lift half the assembly 52", it's still the same amount of work.
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the mass that is being moved would be almost 0, if not positive from the springs.
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The springs don't make the mass zero. They just balance the load and provide an additional source of power. The mass still has inertia.