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Question
In the case of a block and tackle arrangement, the mechanical advantage increases with the number of pulleys. Explain.
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Solution
With the increase in the number of pulleys in the arrangement of block and tackle, the number of strands of string supporting the load increases and so its mechanical advantage increases.
RELATED QUESTIONS
A block and tackle system has V.R. = 5.
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The diagram below shows a pulley arrangement :

(i) Copy the diagram and mark the direction of tension on each strand of the string.
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(ii) Velocity ratio, and
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