WHAT IS A MACHINE?

Machine: A device that makes work easier by changing the size or direction of a force

When you think of a machine, you may think of things such as cars, big construction equipment, or even computers, but not all machines are complicated…..

SIMPLE MACHINES

WORK INPUT & OUTPUT

Work Input: The work being done on a machine

Work Output: The work beingdone by a machine

**In the pictured example, the screwdriver is the machine

MECHANICAL ADVANTAGE

Mechanical Advantage is the number of times a machine multiplies force.

In other words, it compares the input force with the output force.

MECHANICAL ADVANTAGE

A machine has mechanical advantage if the output force is greater than the input force

TYPES OF SIMPLE MACHINES

1) Lever

2) Pulley

3) Wheel and Axle

4) Inclined Plane

5) Wedge

6) Screw

LEVER

Lever: A simple machine that consists of a bar that pivots at a fixed point called a fulcrum

Example: Have you ever seen a nail get removed from a piece of wood with a hammer? If so, the hammer was being used as a lever

PULLEY

Pulley: A simple machine that has a grooved wheel that holds a rope or cable

WHEEL AND AXLE

Wheel and Axle: A simple machine consisting of two circular objects of different sizes; the wheel is the larger of the two circular objects

INCLINED PLANE

Inclined Plane: A simple machine that is a straight, slanted surface, which facilitates the raising of loads.

• Example: A ramp is an example of an inclined plane

WEDGE

Wedge: A simple machine that is made up of two inclined planes and that moves

• Example: Some very commonly used wedges are knives and doorstops

SCREW

Screw: A simple machine that consists of an inclined plane wrapped around a cylinder

• Used most commonly as fasteners

COMPOUND MACHINES

Compound Machine: A machine made of more than one simple machine