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Question
In the fig draw a tackle to lit a load by applying the torce in a convinient direction. Mark the position of load and effort.
(i) If the load is raised by 1 m, Through what distance will the effort move?
(ii) State how many strands of tackle are supporting the load?
(iii) What is the mechanical advantage of the sysytem?
Solution
correct winding of rope around pulleys, load and effort is as shown:
(i) Since there are five strings in the block and tackle system, therefore, the elocity ratio of the system is V.R = n 5
Now, V.R = `"d"_"E"/"d"_"L"`
or, `"d"_"E"` = 5 x `"d"_"L"` = 5 x 1 = 5m
(ii) 5 strands of tackle are supporting the load.
(iii) M . A = L/E
Here, L = 5T, E = T
M.A = `(5"T")/"T"` = 5
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