Today, people in the developed world use machines of ever-increasing complexity to carry out day-to-day tasks conveniently and quickly. Centuries ago, early scientists developed simple machines, including inclined planes, levers and pulleys, that helped reduce the burden of heavy manual work. These building blocks still play a vital part in 21st century technology, each contributing to the capability of more complex equipment. Moving or lifting heavy objects still relies on pulley systems to convert a small force to a large force, often changing the direction of the applied effort.
Mount the bench clamp on the edge of a table or work surface. Ensure the clamp is secure.
Insert the pulley rod into the bench clamp from above. Twist the rod until the pulley wheel, when viewed from above, is at right angles to the edge of the table. Tighten the clamp to secure the pulley.
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Check that the axle of the pulley wheel is horizontal and free to rotate. Ensure there is no obstruction below the pulley wheel.
Tie one end of the string firmly to the weight. Place the weight on the floor directly below the pulley and feed the other end of the string over the pulley wheel from below.
Pull the free end of the string gently over the pulley to take up any slack. Continue to pull the string horizontally so the weight is lifted vertically off the floor. You have converted a horizontal pulling motion into a vertical lifting motion.
If you do not have a rod-mounted pulley and clamp, use LEGO blocks and wheels to build a pulley that can be fixed to the table.
Do not use a heavy weight. If the clamp fails or the string breaks, the weight could fall and injure you.