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Question
A block and tackle system of pulleys has a velocity ratio of 4.
- Draw a labelled diagram of the system indicating clearly the points of application and directions of load and effort.
- What is the value of the mechanical advantage of the given pulley system if it is an ideal pulley system?
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Solution
(a)

(b) M. A. = `"Load"/"Efforts" = (4"T"_"L")/"T"_"E" = 4`
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The alongside figure shows the combination of a movable pulley P1 with a fixed pulley P2 used for lifting up a load W.

(i) State the function of the fixed pulley P2.
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