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In a pulley setup that has a moving pulley, __________.

A.) you have to pull the string a greater distance, but the force needed to lift the mass is cut in half
B.)you have to pull the string a greater distance, and it takes more work to lift the mass
C.) you don't have to pull very much to lift the mass
D.)your work doubles because the pulley moves

Respuesta :

mathmate
The usual setup of moving pulleys will reduce the force needed to lift a load is cut in half, BUT the distance to be moved is doubled.
Thus the same amount of work is required to lift the same load the same distance between pulley setups with or without a moving pulley.
In a pulley setup that has a moving pulley, you have to pull the string a greater distance, but the force needed to lift the mass is cut in half.