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Question
A block and tackle system has 5 pulleys. If an effort 0f 1000 N is needed in the downward direction to raise a load of 4500 N, calculate:
- the mechanical advantage
- the velocity ratio, and
- the efficiency of the system.
Solution
A block and tackle system has 5 pulleys. (n = 5)
Effort = 1000 N
Load = 4500 N
- The mechanical advantage M.A = `"๐๐๐๐"/"๐๐๐๐๐๐ก"`= `4500/1000` = 4.5
- The velocity ratio = n = 5
- The efficiency of the system η = `"๐.๐ด"/"๐.๐
"`= `4.5/5``
= 0.9 ๐๐ 90%
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