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## By: Christina Widder

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### By, the ancient Greek mathematician, Archimedes. ... 'Castle Rock State Park River.' Online Image. 13 Aug. 2006. Rock River. Oct. 2006. ... – PowerPoint PPT presentation

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Title: By: Christina Widder

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 wouldnt 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
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
• 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 lthttp//www.sciencetrek.net/
archimedes
• .htmgt
• 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 lthttp//www.enchantedlearning.
com/physics/machines/
• Levers.shtmlgt
• Col, Jeananda. Zoom Inventors and Inventions.
Enchanted Learning. Oct. 2006 lthttp//www.enchante
dlearning.com
• /physics/machines/Levers.shtmlgt
• Egyptian Pyramid. Online Image. A Visit to the
Pyramids Oct. 2006. lthttp//members.cox.net/ancie
nt-sites/egypt/Pyramid_and_Sphinx.JPGgt

18
Work Cited Continued
• History of Levers. Science Technology and
Engineering. Oct. 2006 lthttp//www.enged.com.au/s
tudents/mecsys/mecsys17.htmlgt
• Johnson, Jerry. Simple machines, work Physical
Science. Oct. 2006. lthttp//www.sirinet.net/jgjo
hnso/simple.htmlgt
• McKee, Jeffery. Lever. Online Image. Science of
Evolution. Oct. 2006. lthttp//home.insight.rr.com/
jkmckee/lever.jpggt
• Roman Scissors. Online Image. Oct. 2006
lthttp//www.petrie.ucl.ac.uk/detail/Images/72/UC36
207.jpggt
• Simple Machines. 7 Oct. 2006. School for
Champions. Oct. 2006 http//www.school-for-champi
ons.com/science/machines.htm
• Third Class. Engine Mechanics. Oct. 2006.
lthttp//www.tpub.com/machines/1b.htmgt
• Wheelbarrow. 7 Oct. 2006. Wikipedia. Oct. 2006.
lthttp//en.wikipedia.org/wiki/Wheelbarrowgt

19
THE END!