Pulleys are grooved wheels that allow ropes, chains, or cables to run through them. There are three types of pulleys: fixed pulleys which do not increase force but change direction, movable pulleys which are attached at one end and do increase force, and block and tackle pulleys which use a combination of fixed and movable pulleys to further increase applied force.

1. Pulleys

2. Definition A pulley is a grooved wheel with a rope, chain, or cable running along the groove.

3. Fixed Pulleys A fixed pulley is similar to a 1 st class lever! The wheel is the fulcrum and the rope on both sides is the effort and resistance! A fixed pulley is attached to something that doesn’t move, like the ceiling or wall Ex: Elevator Fixed pulleys do NOT increase force. They only change direction. Small IMA!

4. Fixed Pulleys

5. Movable Pulleys A movable pulley is one in which one end of the rope is fixed and the wheel is free to move. Movable pulleys DO increase force and therefore can have a large MA!

6. Movable Pulleys

7. Block and Tackle Pulleys Block and tackle pulleys are a combination of fixed and movable pulleys. They can have a large MA!

8. Block and Tackle Pulleys