Page 259 - Bài 1 ok_Neat
P. 259

To achieve the highest MA with the least number of pulleys requires constructing a
               compounded system of a 2:1 simple pulley system acting on a 2:1 simple pulley system,
               acting on a 2:1 and so forth.  As each pulley is added to such a system, the mechanical
               advantage increases exponentially (e.g. 2:1, 4:1, 8:1, 16:1, 32:1, etc.).

               When constructing a compound pulley system, critically think of all the possible
               combinations that when multiplied together will equal your desired MA; then consider
               the advantages and disadvantages of each and determine which combination will best

               meet your needs given your available equipment and working constraints.


















                (a) Compound 4:1 (Simple 2:1 pulling on Simple 2:1)
















                (b) Compund 6:1 (Simple 3:1 pulling on Simple 2:1)




















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