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 ...

Tabloids have seized on the most headline-friendly takeaway - “pulleys built the pyramid” - but the underlying claim is more specific: the pyramid may have grown “inside-out,” using internal sloped ...

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