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Minibyte
Sep12-09, 04:49 PM
Is it easier to pull up or down to lift a weight on a single pulley systeM?

Thanks

MB

russ_watters
Sep12-09, 05:59 PM
The force required is the same.

Minibyte
Sep12-09, 08:38 PM
Hmm. Well, I was given and A and B answer so, it has to be one or the other. I was thinking it was lifting (A) since the force to pull (B) seems to require more force. I could be wrong. I really don't know the answer.

russ_watters
Sep12-09, 09:01 PM
Err, I think I got an incorrect picture in my head of what is going on (which is why it helps to have a diagram!) If the "pull down" scenario is just a rope looped over a pulley, whereas the "pull up" scenario has a pulley on the object, there is a mechanical advantage in the second scenario and thus it is easier to pull up.

Minibyte
Sep12-09, 09:05 PM
Thanks Russ, that was my guess too. Pull up vs pull down. Thank you!