A pulley is a simple machine using a wheel and a cord that's designed for lifting. A pulley is a simple machine using a wheel and a cord that's designed for lifting. Pulleys help make work easier by ...

Explains how pulleys work to lift heavy weights more easily. A fixed pulley changes the direction of force, allowing for easier lifting, while a movable pulley reduces the amount of force needed to ...

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It turns out it’s not that easy to find replacement parts for a bridge built in 1931. Crews working on the $8.7 million rehabilitation of the Stillwater Lift Bridge had to ship its four huge pulleys ...