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Question
A pulley system has a velocity ratio 3. Draw a diagram showing the point of application and direction of load (L), effort (E) and tension (T). It lifts a load of 150 N by an effort of 60 N. Calculate its mechanical advantage. Is the pulley system ideal? Give reason.
Solution
-
Above is a diagram of the block and tackle pulley system with a velocity ratio of 3, along with markers for the directions of load (L), effort (E), and tension (T).
- Given L = 150 N, E = 60 N
Mechanical advantage M.A.
= `"Load"/"Effort"`
= `150/60`
= 2.5 - This is not the ideal pulley system.
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