Part two:
Catapults were first seen in the form of cross bows; the word catapult came from the Greek word “katapultos”. Different types of catapults were seen in Greece, Rome and China, they showed up inn England around the middle ages. The three main types of Catapults were Ballista(Greeks;later modified by the Romans), Trebuchet(Chinese), and the Mangonel(Romans). The first documented catapult was invented by the Greek Dionysius the Elder of Syracuse. Dionysius invented this version of catapult in 399BC and it was called a Gastraphete. The catapult was invented to help win battles by launching heavier projectiles further and destroying castle walls. As castle walls became higher and stronger they needed to build smarter weapons. The catapults launched things such as rocks, burning tar, Dead animals and body parts; the catapult was used in some of the earliest cases of biological warfare, when diseased bodies would be thrown over walls to infect enemies. Catapults were used all other Europe but mostly by the French, until 885-886 when new technology was invented. In the long term the catapult inspired newer and better technology and people such as Archimedes.
Part 3:
The catapult uses Elastic potential energy, Elastic kinetic energy and Elastic force to launch projectiles.
In the version we made, the Mangonel, starts with elastic potential energy. The payload is then pulled back giving it elastic kinetic energy and losing the potential energy. When the payload is released the lever hits the cross bar which causes it to lose a lot of energy; therefor the catapult isn’t very efficient. The payload is pulled back and released using elastic force.
Ep=mgh Ek=1/2mv2 Fs=-kx
Efficiency= (mgh) over (Fd)
Part four:
Day one: Planning/ deciding on machine
Day two: Absent
Day three: We started building. We hot glue gunned the frame together.
Day four: Finished building and tested. It was difficult to get the elastic attached because the Popsicle sticks were a different size than we thought.
Day five: Worked on blog post
Part five:
“History of Catapults – Physics of Catapults.” Google Sites, sites.google.com/site/physicsofcatapults/home/history-of-catapults.
Catapult History and Modern Day Construction, www.midrealm.org/mkyouth/links/catapults.htm.
Smith College Museum of Ancient Inventions: Stone-Hurling Catapult, www.smith.edu/hsc/museum/ancient_inventions/hsc11b.htm.
“Catapult Physics.” Real World Physics Problems, www.real-world-physics-problems.com/catapult-physics.html.
Catapults, www.lordsandladies.org/catapults.htm.
Wilford, John Noble. “How Catapults Married Science, Politics and War.” The New York Times, The New York Times, 23 Feb. 2004, www.nytimes.com/2004/02/24/science/how-catapults-married-science-politics-and-war.html.