## My CatapultBy:Mariana Peters

#### Introduction

• Romans won wars
• smartest war weapon destroy cities
• Weapon was a catapult.
• Romans changed how wars were fought
• history lesson
• Science presentation.

#### Physics Concepts

This is a Trebuchet catapult.
• And for the Trebuchet the formula is X*V*Ti
• Vx is equal to the initial velocity times the cost of θ.
• If we assume air resistance is negligible.
• Then the v(x ) component won’t change during the launch.
This a Mangonel catapult.
• For Mangonel the formula is F=k(x)
• The arm has to be at a 45॰angle
• In order for the arm to throw the ball 5 meters

#### History of the Catapults

• It was invented by the Romans
• At least 1,300 ft.
• maximum force
• Rocks for throwing
• Cities it killed a lot of people

This video is an example of a Trebuchet.

This shows a example of a Mangonel

#### Qualitative Data

This is my Qualitative Data

This is my graph

#### My Diagram Photo

My catapult
• Parts of my catapult.
• 11 different brackets; 10 L brackets and one Hinge.
• brackets hold the wood in place,reinforced screws; the hinge holds the arm in place.
• wood that stops the arm at 45 degrees
• bottom of the catapult there are 4 rubber feet
• Counter weights hold the catapult down.
• Moved spring to outer eye hooks
• Tested again
• Tested again
• Change the angel about 48 degrees
• Changed holder for ball less depth

#### My Catapult Test Videos And Photos

This is my catapult

#### Videos

This is test number 2

This is test number 1

#### Conclusion

• Spring/bungee stretched back equals more potential energy
• When released compression potential energy turns into knit energy
• launching the lever
• transferred from spring to the arm into the tennis ball
• Constructing my catapult the is trick was to find the proper length of the arm
• Tension-spring or bungee best launching angle approx. 45 degrees

If you want to throw eggs and stuff at your siblings go build a catapult.

Credits:

Created with images by dakzxz - "sunset novovoronezh summer" • juliacasado1 - "trebuchet catapult medieval weapon" • ryochiji - "IMG_1454.JPG"