The Catapult
During the past week in physics class we were challenged to construct an invention from a list of various inventions ranging from a simple lever system to the invention of the steam engine. My group chose to make a mangonel catapult. This catapult was invented in 400 BC by the ruler of Syracuse, Dionysius. The purpose of the catapult was to hurl projectiles long distances and over walls and through them. the invention of the catapult led to people wanting objects thrown harder, farther, and with more accuracy. This lead the invention of gunpowder was invented in the 14th century putting all catapults to rest and destroying all need for them having them replaced with canons which were more accurate, and easier to move.
The process…
Day 1 – Stan and I drafted different types of catapults we could make and finalized our decision on the mangonel catapult.
Day 2 – Find and mark wood to the appropriate lengths for the mangonel catapult
Day 3 – assembly of parts
Day 4/5 – test and assess
Pictures on Drive link ( click here )
The Physics…
The physics behind a mangonel catapult is the following: an applied force acts on the arm of the catapult bringing it back into the throwing position gaining potential energy all the way down. Once the arm is released, that potential stored energy is converted into kinetic energy as the projectile is launched. However, not all of the energy goes into the projectile. Some of this energy is lost to the recoil of the catapult as the launch arm collides with the brace and some energy is lost to sound. The initial velocity of the projectile is equal to the velocity of the cup at the end of the launch arm. Once launched, the projectile is acted upon by air resistance as it travels through the air while the force of gravity pulls it down towards the earth’s surface.
Below are the sites referenced from.
https://www.real-world-physics-problems.com/catapult-physics.html
https://en.wikipedia.org/wiki/Mangonel
https://sites.google.com/site/physicsofcatapults/home/how-a-catapult…the…/mangonel
https://sites.google.com/site/physicsofcatapults/home/history-of-catapults