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By: Christina Widder

Levers in History. By: Christina Widder. A lever is…. A simple machine. A rigid bar pivoted about a fulcrum. Broken up into three classes. Three Classes of Levers. A first class lever is the most common type of lever. First Documented Knowledge of levers. Was in 260 B.C.

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By: Christina Widder

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  1. Levers in History By: Christina Widder

  2. A lever is… • A simple machine. • A rigid bar pivoted about a fulcrum. • Broken up into three classes.

  3. Three Classes of Levers A first class lever is the most common type of lever.

  4. First Documented Knowledge of levers • Was in 260 B.C. • By, the ancient Greek mathematician, Archimedes. • In this picture a first class lever is being used.

  5. When was the first lever made? • The real answer is uncertain. • But it is believed that the first use of levers used trees to move heavy rocks. • Once again a first class lever is being used in the picture to the right

  6. Ancient Egyptians • Levers helped build the pyramids. • Levers were used to lift large rocks for building. • Then they used other simple machines to transport those rocks.

  7. Ancient Egyptians • It was estimated that it took about 30 years to build the pyramids with levers and other simple machines. • But what if levers did not exist then? • Image how long it would have taken to build the pyramids, if it was even possible.

  8. Ancient Egyptians • Egyptians also used levers to move water from rivers.

  9. Ancient Egyptians • This would be a lever with a counterweight. • The weight being on the opposite side of the bucket would make it easier to lift the water.

  10. Ancient Egyptians • After the water is lifted, the pole is moved to the other side where the water can be put into the channel, which is then more accessible. • It was estimated that one person could lift 2,500 liters of water a day. • Without a lever a person probably wouldn’t be able to lift as much water.

  11. Ancient Romans • The first simple catapult was invented in Ancient Greece. • But the Romans used levers in making catapults with wheels, along with other simple machines.

  12. Ancient Romans • The catapults were used to throw large rocks at their enemies. • Catapults helped the Romans defeat many armies.

  13. Modern Scissors • Are made from two cross-blades that pivot around a fulcrum (two levers). • Were invented in ancient Rome around A.D. 100. • Scissors were typically used to make clothing.

  14. Wheelbarrow • The Chinese were credited for the invention of the wheelbarrow in A.D. 100. • The wheelbarrow is a second class lever, but also has a wheel and axle. • Was used to transport rocks, or even medical supplies during wars.

  15. Your Arm is a lever • The fulcrum would be the elbow, the effort is the muscle, and the load is in the hand. • This is a third class lever. • It is unknown how long humans have been around, but we know that it has been for many, many years.

  16. Conclusion • Levers have been helpful and important throughout history. • Levers help decrease the effort it takes to move, lift, and etc… • There are many other types levers that were used in the past and are still present today; only a few were mentioned here.

  17. Work Cited • Archimedes. Oct. 2006 <http://www.sciencetrek.net/archimedes .htm> • “Catapults.” Online Image. Hardware.fr. Oct. 2006. http://us.games2.yimg.com • “Castle Rock State Park River.” Online Image. 13 Aug. 2006. Rock River. Oct. 2006. http://pages.ripco.net/~jwn/rock.jpg • Col, Jeananda. Levers: Simple Machines. Enchanted Learning. Oct. 2006 <http://www.enchantedlearning.com/physics/machines/ Levers.shtml> • Col, Jeananda. Zoom Inventors and Inventions. Enchanted Learning. Oct. 2006 <http://www.enchantedlearning.com /physics/machines/Levers.shtml> • “Egyptian Pyramid.” Online Image. A Visit to the Pyramids… Oct. 2006. <http://members.cox.net/ancient-sites/egypt/Pyramid_and_Sphinx.JPG>

  18. Work Cited Continued • History of Levers. Science Technology and Engineering. Oct. 2006 <http://www.enged.com.au/students/mecsys/mecsys17.html> • Johnson, Jerry. Simple machines, work… Physical Science. Oct. 2006. <http://www.sirinet.net/~jgjohnso/simple.html> • McKee, Jeffery. “Lever.” Online Image. Science of Evolution. Oct. 2006. <http://home.insight.rr.com/jkmckee/lever.jpg> • “Roman Scissors.” Online Image. Oct. 2006 <http://www.petrie.ucl.ac.uk/detail/Images/72/UC36207.jpg> • Simple Machines. 7 Oct. 2006. School for Champions. Oct. 2006 http://www.school-for-champions.com/science/machines.htm • Third Class. Engine Mechanics. Oct. 2006. <http://www.tpub.com/machines/1b.htm> • Wheelbarrow. 7 Oct. 2006. Wikipedia. Oct. 2006. <http://en.wikipedia.org/wiki/Wheelbarrow>

  19. THE END!

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