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Question
Give reason for the following:
In case of a block and tackle system, the mechanical advantage increases with the increase in the number of pulleys.
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Solution
In a block and tackle system, if the total number of pulleys used in both the blocks is 'n' and the effort is being applied in the downward direction, then the tension in and segments of string support the load. therefore
L = n T and E = T
M.A = `"load"/"effort" = "nT"/"T" = "n"`
Thus in a block and tackle system, the M.A is equal to the number of pulleys and it increases with the increase in the number of pulley.
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