A movable pulley is combined with a fixed pulley to lift a heavy engine block weighing $400\text{ N}$.…
A movable pulley is combined with a fixed pulley to lift a heavy engine block weighing $400\text{ N}$. Ignoring friction, what minimum upward force must be applied to the free end of the rope?
$400\text{ N}$
$800\text{ N}$
$200\text{ N}$
$100\text{ N}$
Solution
A single movable pulley supports the load with two rope segments, sharing the load equally and reducing the required effort force by half: $400\text{ N} / 2 = 200\text{ N}$.