Pulleys question - Need a rig to lift with a MA=107?

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The discussion revolves around creating a rig to lift a 3200lb weight using a 30lb weight, requiring a mechanical advantage (MA) of 107. It is confirmed that pulling the 30lb weight down 107cm would indeed raise the 3200lb weight by only 1cm. The main inquiry is whether it's possible to increase the movement of the heavier weight without raising the force needed. The consensus is that there is no method to achieve this without increasing the force required. The conversation highlights the limitations of pulley systems in achieving desired mechanical advantages.
gruff
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Hi

I have an installation/art project that requires a rig designed to balance a weight of 3200lbs using a weight of 30lbs. I think that means a mechanical advantage of 107 if using pulleys? Both weights would be suspended in the air by the rig so that someone pulling on the small weight would make the heavy weight move upwards perceptibly.

As I understand it (which is not very well!) if you pulled on the 30lb weight and moved it down 107cm the 3200lb weight would move up only 1cm. Is that right?

My question then: is there a way to make the heavy weight move more for a given movement of the lighter weight without increasing the force required?
 
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gruff said:
As I understand it (which is not very well!) if you pulled on the 30lb weight and moved it down 107cm the 3200lb weight would move up only 1cm. Is that right?

Yes.


gruff said:
My question then: is there a way to make the heavy weight move more for a given movement of the lighter weight without increasing the force required?

No.

CS
 
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