Physics
You are given four pulleys and three strings. Draw a neat and labelled diagram to use them so as to obtain a maximum mechanical advantage equal to 8. In your diagram mark the directions of load L, effort E and tension in each strand. What assumptions have you made to obtain the required mechanical advantage?
Machines
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Answer
The four pulleys can be used as three movable pulleys with one fixed pulley as shown in the diagram below:
Assumptions are —
(i) The weight of the pulleys and the string is massless.
(ii) There is no friction between the bearings of the pulley.
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