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

AI Thread Summary
The pulley system with the least force required to lift the same weight is system E, which has the highest mechanical advantage (MA) of 3. The mechanical advantages of the other systems are lower, with A at 1 and B, C, and D at 2. The key to solving this problem is recognizing that the pulley connected to the ceiling only changes the direction of the rope and does not contribute to the mechanical advantage. In system E, three strings support the weight, resulting in the smallest tension needed to lift the load. Understanding the role of mechanical advantage is crucial in determining the efficiency of different pulley systems.
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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?
 
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