Movable Pulleys - Simple Machines - What are pulleys? How do pulleys work?
Quatr.us answers questions

Movable Pulleys

Bike hoist pulleys
Bike hoist pulleys

November 2016 - A movable pulley is a way to use a pulley to make it easier to move heavy things - to get a mechanical advantage. In the picture, someone is trying to pull their bike up to the ceiling so it will be out of the way. They've used two fixed pulleys, attached to the ceiling, and two movable pulleys, hooked on to their bike.

The fixed pulleys make it easier to pull the bike up, by changing the direction of force so he can pull down instead of having to lift the bike up. But the movable pulleys give him a mechanical advantage too:

Here's a video of someone actually using a bike hoist:

Learn by doing - pulleys
Fixed pulleys
More about simple machines

Bibliography and further reading about simple machines:

Machines
Physics
Quatr.us home


Professor Carr

Karen Eva Carr, PhD.
Assoc. Professor Emerita, History
Portland State University

Professor Carr holds a B.A. with high honors from Cornell University in classics and archaeology, and her M.A. and PhD. from the University of Michigan in Classical Art and Archaeology. She has excavated in Scotland, Cyprus, Greece, Israel, and Tunisia, and she has been teaching history to university students for a very long time.

Professor Carr's PSU page

Help support Quatr.us!

Quatr.us (formerly "History for Kids") is entirely supported by your generous donations and by our sponsors. Most donors give about $10. Can you give $10 today to keep this site running? Or give $50 to sponsor a page?

Quatr.us stands with women and people of color everywhere: we are all more free when all of us are free. Honoring strong women of color like Enheduanna in Iraq, Ankhesenpepi and Hatshepsut in Egypt, Shanakdakhete in Sudan, Wu Chao and Cixi in China, Pari Khan Khanum in Iran, Suiko in Japan, Chand Bibi and Hamida Banu in India, and Yaa Asantewaa in Ghana.