Simple machines power point

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Rosa Ruiz Diaz & Wanda Valdez
Brooklyn College
Fall 2008
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.


Simple machines are grouped into six types:
1.
Lever
2.
3.
4.
5.
6.
Inclined Plane
Wheel and Axle
Screw
Wedge
Pulley
Simple machines are tools that use energy to
do work.
 Energy is the ability to do work.

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.
1. First Class Lever.
 2. Second Class Lever.
 3. Third 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.
●
In a second class lever the fulcrum is at the
end, with the load in the middle.
 Think of a wheelbarrow.

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

An inclined plane is a flat surface that is higher
on one end
 Inclined planes make the work of moving things
easier


A wheel and axle is a simple machine made of
a rod attached to the center of a wheel.
A screw is an inclined plane wrapped
around a shaft or cylinder.
 The inclined plane allows the screw to
move itself when rotated.

Two inclined planes joined back to
back.
 Wedges are used to split things.


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.

It a combination of simple machines that
work together.



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



http://www.kn.att.com/wired/fil/pages/listamazingwa1.html
Inclined plane
Screw
Wheel and axel
Pulley
Wedge
Inclined plane
NSF North Mississippi GK-8
They help us do work.
 They make our lives easier.
 Let’s see how many times we use simple
machines in our lives.

7
6
6
5
4
morning
afternoon
evening
3
2
1
1
0
0
blender
0
scissors
bicycle
sharpener


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/Mechan
icaladvantage
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