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alephnull
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Homework Statement
For some reason, this question's really stumped me. The text reads:
"The system shown is in static equilibrium. Use the principle of virtual work to find the weights A and B. Neglect the weight of the strings and the friction in the pulleys."
And has the accompanying diagram:
http://img143.imageshack.us/img143/9292/path2405.png
EDIT: oops; that 40° should read 45°; sorry about that.
For variables, I think we have:
A and B (obviously)
Perhaps rope tension?
Homework Equations
Not sure, to be honest.
The Attempt at a Solution
Based on what I've looked at previously with the principle of virtual work, I'd say I would have to generate a pair of equations based on the imagined movement of the weights and then solve the two simultaneously to get the values for A and B, but it's here it all falls down: I can't figure out how far the 1kg weight would rise if weight A fell, say, 2 metres. Of course, this method could be fundamentally flawed anyway and it wouldn't really matter.
(Yes, this is the second exercise from the exercise section of Feynman's Tips on Physics; having picked up the Feynman Lectures to try and learn some more advanced physics on my own than what is being taught in my school, there are more than a few gaps in my knowledge which lead to situations such as this where the question seems only tangentially related the the actual lecture)
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