Which pulley system requires the least force to lift the same weight?

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zizodev
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Homework Statement



http://data.imagup.com/10/1146555432.jpg

Homework Equations



Force applied on the weight=F*(MA).

The Attempt at a Solution


i chosse the E system ...it has the greater mechanical advantage (MA)=3.
MA(of A)=1, MA(of B)=2,MA(C)=2,MA(D)=2,MA(E)=3..
I hope my suggestions are correct ! :)
 
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I agree with you. The 'trick' in these question is to ignore the pulley connected to the ceiling, this pulley simply changes the direction of the rope.
Count the number of strings holding up the weight, in E it is 3... Therefore this needs the smallest tension in the string (1/3 the weight)
 
What do you think F = m a hass to do with this problem?