What are the Simple Machines?
Nadeen A., 2012
There are many different types of simple machines; they are the lever, pulley, inclined plane, wedge, wheel and axle, screw. I am only going to right about three of the simple machines and they are a lever, pulley, and inclined plane. All of the simple machines are called simple because they contain only one simple machine.
What is a lever?
A lever is a type of simple machine that contains a fulcrum. A fulcrum is a base that can be moved depending on the weight of the object that is being lifted. You could move the fulcrum closer to the object and you will have more force to move the object. A lever has many different uses for example one use is as a seesaw another use is scissors. The lever appeared in about 5000 B.C. The lever has many classes including the l class lever the ll class lever and the lll class lever.
The lll class lever has the input force between the output force and the fulcrum. Another example of a lever is a crow bar. Also in the diagram below one lever shows equal forces and another shows unbalanced forces.


LEVER.jpg
Figure 1: One equal balance and an unbalanced lever

What is an inclined plane? An inclined plane is also a ramp. An inclined plane uses a ½ the weight that you would use to pull the object upward. One advantage to the inclined plane is that it is equal to the ratio. Also the inclined plane consists of a sloping surface. The steeper the slope the faster the required force reaches the actual weight. Also the slope is either less equal to, or greater than 45 degrees. The inclined plane was created with two sides that are exactly the same; also
the inclined plane also was made to lift heavy bodies and objects.

Inc.jpg
Figure 2: A ramp that lifts heavy items

pulley.jpg
Figure 3: : Pulley with equal weights and Pulleys with uneven weights.



What is a pulley?
A pulley has to overcome the force of gravity in to lift the object. In a pulley one side does the pulley pulls and on the other side the pulley pushes. Also the pulley has one wheel to help the ropes. For example if you wanted to take a piano to the 4th floor would you lift by a pulley or would you put it on a ramp? You would of course you would use a pulley because the pulley would allow you to take the piano automatically to the 4th floor, but with a ramp you would be crushed trying to get a piano to the 4th floor. Also the amount of force you use is equal to the weight. One advantage for the pulley is that it moves things both frontward and backward. The first crane was invented in about 1000 B.C.

These are the simple machines that were going to talk about. Also the simple machines are not just three but six. Here is a picture of all the simple Machines.



simplemachines.gif
Figure 4: All the simple machines






Glossary
Fulcrum: The point in a lever.
Inclined plane: A ramp structure that uses only ½ the effort you would use to pull the object straight upward.
Lever: A simple machine that has a point called the fulcrum and the closer you put the fulcrum to the object the more force you have.
Pulley: A simple machine that pulls the force upward and the pulley needs to overcome the force of gravity.


Books
Ardley, Neil. How things Work. Pleasantville: NY readers Digest 1995

Knight, Judson. Science everyday things volume (2) real life physics. Detroit: Gale Group 1996

Databases

Encyclopædia Britannica, Inc., 2012. Web. 24 Sept. 2012.
"mechanics." Compton's by Britannica. Encyclopædia Britannica Online School Edition.


Website
Wikipedia contributors. "Simple machine." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 21 Sep. 2012. Web. 24 Sep. 2012.