1. Classification of simple machines: Simple machines are divided into two families: 1)The Lever family and 2) The inclined plane family

2. The classes of Lever First class of Lever: It has
fulcrum located between the
input force and the output force.
• Second class lever: The fulcrum
Is at one end of the arm and
Input force is applied to the
other end, ex. Wheelbarrow.
• Third class of lever: The input
force is in between fulcrum and
output force.

3. Types of Pulleys and their MA
Fixed pulley: The pulley is fixed with support. It has MA = 1 since used to change direction of force.
Movable single Pulley: The pulley is not fixed with support, it can increase the MA, the load is shared by two sections of rope pulling upward.

4. Block and tackle
Using movable pulleys or more than one pulley at a time can increase the mechanical advantage.
Multiple pulleys combined into a single unit is called a Block and tackle.
All of the sections of rope are pulling up against the downward force of the weight.

5. Wheel and Axle A wheel and axle is a lever
connected to a shaft. A wheel
and axle is made of a lever or
A pulley (wheel) connected to
A shaft (the axle)
• When the wheel is turned, the
Axle also turns.
• When a small input force is applied to a steering wheel, the force is multiplied to become a large output force which turns the front wheel of the car. Other ex: screw driver