What is WORK?Occurs when a FORCE causes an object to

move

What is FORCE?A PUSH or a PULL on an object

What is a Simple Machine? A tool that helps make work easier

•A machine makes work easier by changing the size or direction (or both) of a force

•The FORCE and OBJECT have to go the SAME direction

WORKWORK

•Machines do NOT save work. They just make work EASIER

•The SAME amount of work is still done

Have you ever used a ramp to load a heavy object into a pick-up truck?

Types Of Simple Machines

All machines are made from these 6 simple tools:

1. Lever2. Inclined plane3. Wedge4. Screw5. Wheel and axle6. Pulley

Pulleys•A simple machine consisting of a wheel that holds a rope • changes the direction and/or amount of force needed to lift an object

3 types of pulleys:

1. Fixed Pulley

2. Movable Pulley

3. Block and Tackle

Pulleys

http://www.youtube.com/watch?v=9T7tGosXM58

What is a Pulley?A pulley consists of a rope wrapped around a grooved wheel.The rope of chain is wrapped around the wheel, and one end is attached to the load.The other end is pulled to move the load.

Why Use a Pulley

• A pulley can change either the size or the direction of a force.

Pulley Systems• More than one pulley can be used in a pulley

system to reduce the force needed even more. • The more pulleys in a system, the greater the distance you will have to pull the rope.

A simple machine that is a straight, slanted surface

The longer the inclined plane is compared to its height, the easier it is to make to the tophttp://www.youtube.com/watch?v=pG_kT565-XQ

What is an INCLINED PLANE?

• An inclined plane is a simple machine with a flat slanted surface.

Inclined Plane

• Inclined planes reduce the force needed and to make work easier.

• The longer the plane the greater the distance and the less force needed.

Inclined Plane

Some examples of an inclined plane are

Simple Machines Reflection

Pulley Inclined Planes1. Definition2. Draw at least 3

real world examples of a pulley

3. Write 1 sentence for each picture explaining how it makes work easier

1. Definition2. Draw at least 3

real world examples of inclined planes

3. Write 1 sentence for each picture explaining how it makes work easier