How Pulleys Are Constructed

A common pulley

Pulleys have been used throughout history to make impossible jobs possible. The basic construction of a pulley is simple; a rope, belt or chain is wrapped around a wheel. It is a simple concept, but the pulley has made the moving of big objects much easier.

Fixed Pulley

Fixed pulleys are constructed by attaching the wheel to an immovable object, such as a ceiling. This helps stabilize the pulley and allows for more weight to be lifted, but more effort is needed to pull the object up.

Movable Pulley

A movable pulley is constructed with the wheel attached to the object that is being lifted. This means that there is less effort going into the load, but the pulley has to be pulled up and down instead of the rope.

Combined Pulley

The combined pulley uses two wheels with the rope intertwined between them, utilizing elements of both the fixed and the movable pulley types. This method uses less effort but requires more room to work.

References

• The Office: Pulley Basics
• Science Experiments: How to Make a Pulley

Resources

• Read this Article in Spanish