There are three types of pulleys: fixed pulleys, which change the direction of an applied force but do not move with the load; movable pulleys, which move along the rope together with the load and multiply the applied force without changing its direction; and block and tackle systems, which use a combination of fixed and movable pulleys to lift very heavy loads with increased force but at the cost of speed.

1. PULLEY

2. PULLEY
kind of wheel that turns
on an axle

3. 3 Kinds of Pulley

4. Fixed Pulley
- does not travel with the
load.
- changes the direction of the
applied force.

5. Example:

6. A FLAGPOLE IS A FIXED PULLEY
BECAUSE ……
- in a flagpole, there is a fixed pulley at the
top of the flagpole. The flag which is
attached to the other end of the rope
moves up as the other end of the rope is
pulled down and if the other end is
pulled up the flag goes down.

7. MOVABLE PULLEY
- moves along the rope together with
the load
- used to multiply the applied force
-does not change the direction of the
applied force

8. MOVABLE PULLEY

9. BLOCK AND TACKLE
A combination of fixed and
movable pulleys.

10. BLOCK AND TACKLE
ADVANTAGES DISADVANTAGES
Can lift heavy loads easier
than a single pulley
Takes a longer time to
raise a heavy load
Gain in force Loss of speed in raising an
object