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Question
In which direction does the force need to applied, when a single pulley is used with a mechanical advantage greater than one? How can you change the direction of force applied without altering its mechanical advantage? Draw a labelled diagram of the system.
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Solution
A single movable pulley can be used to obtain an M.A. greater than 1, but this is impractical as it requires exerting force in an upward direction. Instead, a fixed pulley is used in conjunction with the movable pulley to apply force in a downward direction.
The only purpose of a fixed single pulley is to shift the force's application direction in a direction that is convenient.
M.A. = `(2T)/T = 2`
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