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View Full Version : Pulleys question - Need a rig to lift with a MA=107?


gruff
Nov15-09, 05:15 AM
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?

stewartcs
Nov17-09, 09:57 AM
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.



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