SIMPLE MACHINES

Rosa Ruiz Diaz & Wanda ValdezBrooklyn CollegeFall 2008

WHAT IS A SIMPLE MACHINE

Is a mechanical device that helps us do work by helping us move things easier, faster or father. A simple machine has few or no moving parts.

TYPES OF SIMPLE MACHINES

Simple machines are grouped into six types:

1. Lever

2. Inclined Plane3. Wheel and Axle4. Screw 5. Wedge6. Pulley

ENERGY AND WORK

Simple machines are tools that use energy to do work.

Energy is the ability to do work.

WHAT IS A LEVER?

A rigid bar that rotates on a pivot called a fulcrum.

All levers have four parts:1. A rigid bar, called the arm.2. The fulcrum, or support around which the

arms pivot.3. The load, which is the object to be moved.

4. The effort, or force that is applied to move the load.

THERE ARE THREE CLASSES OF LEVERS

1. First Class Lever. 2. Second Class Lever. 3. Third Class Lever.

FIRST CLASS LEVER

●In a first class lever the fulcrum is in the middle and the load and effort is on either side.●Think of a see-saw.

SECOND CLASS LEVER

In a second class lever the fulcrum is at the end, with the load in the middle.

Think of a wheelbarrow.

THIRD CLASS LEVER

In a third class lever the fulcrum is again at the end, but the effort is in the middle

Think of a pair of tweezers

INCLINED PLANE

An inclined plane is a flat surface that is higher on one end

Inclined planes make the work of moving things easier

WHEEL AND AXLE

A wheel and axle is a simple machine made of a rod attached to the center of a wheel.

SCREW

A screw is an inclined plane wrapped around a shaft or cylinder.

The inclined plane allows the screw to move itself when rotated.

WEDGE

Two inclined planes joined back to back.

Wedges are used to split things.

PULLEY

A pulley is a circular lever that consists of a grooved wheel rotating about a hub.

A pulley needs a rope, chain or belt around the groove to make it do work.

COMPOUND MACHINES

It a combination of simple machines that work together.

SEARCH FOR SIMPLE MACHINES

Do you think that you are ready to take a quiz on your filamentality website?

Let’s see http://www.teachersdomain.org/collection/k12/

sci.phys.energy.work/

http://www.youtube.com/watch?v=72zNEactb-k http://www.edheads.org/activities/simple-machines/ Or http://www.quia.com/quiz/110999.html?AP_rand=1051613213

FILAMENTALITY

http://www.kn.att.com/wired/fil/pages/listamazingwa1.html

IDENTIFYING SIMPLE MACHINES

NSF North Mississippi GK-8

Inclined plane Wheel and axel Wedge

Screw Pulley Inclined plane

DO YOU KNOW THAT SIMPLE MACHINES ARE IMPORTANT TO US IN OUR DAILY LIFE?

They help us do work. They make our lives easier. Let’s see how many times we use

simple machines in our lives.

THIS IS OUR RESULT

blender scissors bicycle sharpener0

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morningafternoonevening

SOURCES

Mikids.com. 2006. Simple Machines. Accessed 2 February 2006. http://www.mikids.com/Smachines.htm

Wikepedia. Accessed 3 February 2006.

http://en.wikipedia.org/wiki/Mechanicaladvantage