Katapultos

What is a catapult? A catapult is any kind of device that shoots or launches a projectile by mechanical means, a great distance without the aid of explosive devices. The word 'Catapult' comes from the two Greek words "kata" (downward) and "pultos" (a small circular battle shield). Katapultos was then taken to mean "shield piercer".

There are three main types of catapults And 2 sub categories of catapults

The Ballista Similar to a giant crossbow. Tension powered. Launched darts. Comes from the Greek word “Ballistes”, which means “to throw”.

http://www.bownet.org/jvulgamore/armor%20and%20weapons/animated_ballista.htm

Springald Sub-category of the Ballista. Meant to fire darts from inside fortress walls. Since only 1 drawing exist and a later drawing is based off the original drawing, it is believe to only have been a theoretical device.

Mangonel Torsion powered. Hurled objects from a cup on an arm. 1,300 foot range. Capabilities in between a Bastilla and a Trebuchet. From the Latin word “manganon”, meaning “an engine of war”.

Mangonel Torsion powered. Hurled objects from a cup on an arm. 1,300 foot range. Capabilities in between a Bastilla and a Trebuchet. From the Latin word “manganon”, meaning “an engine of war”. http://www.howtobuildcatapults.com/catapultmangonelanimation.html

Early basis for the Mangonel. Onager Early basis for the Mangonel. Originally used a sling, which was later changed to the bucket used for the Mangonel

http://www.howtobuildcatapults.com/catapultonageranimation.html

Comes from the French word “Trebucher” meaning “throw over”. Trebuchet Gravity powered sling. Comes from the French word “Trebucher” meaning “throw over”.

http://www.redstoneprojects.com/trebuchetstore/treb_animated.html

Questions What is a catapult? List 3 types of catapults: Answer first two questions on worksheet

Definitions Force (F): strength or power applied upon an object. F = mass * acceleration

Definitions Mass (m): the quantity of matter (atoms/particles) in the object Gravity (g): the FORCE of attraction by which bodies tend to fall toward the center Elephant vs. Feather no air resistance: http://www.physicsclassroom.com/mmedia/newtlaws/efff.cfm Which has the greater mass the elephant or the feather? Suppose that an elephant and a feather are dropped off a very tall building from the same height at the same time. Suppose also that air resistance could somehow be eliminated such that neither the elephant nor the feather would experience any air drag during the course of their fall. Which object - the elephant or the feather - will hit the ground first? The animation at the right accurately depicts this situation. The motion of the elephant and the feather in the absence of air resistance is shown. Further, the acceleration of each object is represented by a vector arrow. Many people are surprised by the fact that in the absence of air resistance, the elephant and the feather strike the ground at the same time. Why is this so? This question is the source of much confusion (as well as a variety of misconceptions). Test your understanding by making an effort to identify the following statements as being either true or false.   TRUE or FALSE: The elephant and the feather each have the same force of gravity. The elephant has more mass, yet both elephant and feather experience the same force of gravity. The elephant experiences a greater force of gravity, yet both the elephant and the feather have the same mass. On earth, all objects (whether an elephant or a feather) have the same force of gravity. The elephant weighs more than the feather, yet they each have the same mass. The elephant clearly has more mass than the feather, yet they each weigh the same. The elephant clearly has more mass than the feather, yet the amount of gravity (force) is the same for each. The elephant has the greatest acceleration, yet the amount of gravity is the same for each. If you answered TRUE to any of the above, then perhaps you have some level of confusion concerning either the concepts or the words force, weight, gravity, mass, and acceleration. In the absence of air resistance, both the elephant and the feather are in a state of free-fall. That is to say, the only force acting upon the two objects is the force of gravity. This force of gravity is what causes both the elephant and the feather to accelerate downwards. The force of gravity experienced by an object is dependent upon the mass of that object. Mass refers to the amount of matter in an object. Clearly, the elephant has more mass than the feather. Due to its greater mass, the elephant also experiences a greater force of gravity. That is, the Earth is pulling downwards upon the elephant with more force than it pulls downward upon the feather. Since weight is a measure of gravity's pull upon an object, it would also be appropriate to say that the elephant weighs more than the feather. For these reasons, all of the eight statements are false; there is an erroneous part to each statement due to the confusion of weight, mass, and force of gravity. Matter = all material substances that occupy space (anything that has mass and occupies volume) Weight = is the force on an object due to the gravitational pull of a planet or other heavenly body a = change in velocity/ time) a = gravity = 9.81 m/s2 (constant acceleration)

With Air Resistance Definitions Elephant vs. Feather no air resistance: http://www.physicsclassroom.com/mmedia/newtlaws/efff.cfm Suppose that an elephant and a feather are dropped off a very tall building from the same height at the same time. Suppose also that air resistance could somehow be eliminated such that neither the elephant nor the feather would experience any air drag during the course of their fall. Which object - the elephant or the feather - will hit the ground first? The animation at the right accurately depicts this situation. The motion of the elephant and the feather in the absence of air resistance is shown. Further, the acceleration of each object is represented by a vector arrow. Many people are surprised by the fact that in the absence of air resistance, the elephant and the feather strike the ground at the same time. Why is this so? This question is the source of much confusion (as well as a variety of misconceptions). Test your understanding by making an effort to identify the following statements as being either true or false.   TRUE or FALSE: The elephant and the feather each have the same force of gravity. The elephant has more mass, yet both elephant and feather experience the same force of gravity. The elephant experiences a greater force of gravity, yet both the elephant and the feather have the same mass. On earth, all objects (whether an elephant or a feather) have the same force of gravity. The elephant weighs more than the feather, yet they each have the same mass. The elephant clearly has more mass than the feather, yet they each weigh the same. The elephant clearly has more mass than the feather, yet the amount of gravity (force) is the same for each. The elephant has the greatest acceleration, yet the amount of gravity is the same for each. If you answered TRUE to any of the above, then perhaps you have some level of confusion concerning either the concepts or the words force, weight, gravity, mass, and acceleration. In the absence of air resistance, both the elephant and the feather are in a state of free-fall. That is to say, the only force acting upon the two objects is the force of gravity. This force of gravity is what causes both the elephant and the feather to accelerate downwards. The force of gravity experienced by an object is dependent upon the mass of that object. Mass refers to the amount of matter in an object. Clearly, the elephant has more mass than the feather. Due to its greater mass, the elephant also experiences a greater force of gravity. That is, the Earth is pulling downwards upon the elephant with more force than it pulls downward upon the feather. Since weight is a measure of gravity's pull upon an object, it would also be appropriate to say that the elephant weighs more than the feather. For these reasons, all of the eight statements are false; there is an erroneous part to each statement due to the confusion of weight, mass, and force of gravity. Matter = all material substances that occupy space (anything that has mass and occupies volume) Weight = is the force on an object due to the gravitational pull of a planet or other heavenly body a = change in velocity/ time) a = gravity = 9.81 m/s2 (constant acceleration)

CAR 1 Definitions CAR 2 CAR 3 Velocity (v): how far you go over a set amount of time (v = distance/time) Acceleration (a): “speeding up” Which car or cars (red, green, and/or blue) are undergoing an acceleration? Study each car individually in order to determine the answer. Only the green and blue car accelerate, the red car moves at a constant speed, thus is not accelerating. The blue and green cars are speeding up. 2. Which car (red, green, or blue) experiences the greatest acceleration? The blue car (car on the bottom)

Definitions Tension: the state of being stretched or strained. (left) Angles (θ): the space within two lines (right)

Projectile Motion Projectile motion refers to the motion of an object projected into the air at an angle.

Examples: Projectiles in Motion   Soccer Player Long Jumper

Projectiles in Motion  

Projectiles In Motion   Human Cannon

Projectiles In Motion  

Putting it All Together Gravity is necessary to make a projectile land back on the ground. The launching force and angle along with the mass of the object help determine how far and how high the projectile will fly Without Gravity VS. With Gravity

Questions 3. What are 3 factors that will affect the distance the projectile travels? 4. Describe how an object’s mass will change the projectile’s distance traveled? 3. Angle, Initial velocity (Force), and mass These are the worksheet questions

Factors in Affect…What Happened? In order for the tennis player to hit the ball at two different trajectories but land in the same location the player had to hit the ball at a different angle, and most likely used a different amount of force as well.

Factors in Affect….What Happened? In the diagram an object is thrown from the same location, but lands further and further away from its starting place. In order for this to occur the object must be thrown with more and more speed each time. An object of the same mass and same angle is thrown faster and faster each time

Questions Answer Question 5 6. Describe how tension affects the projectile motion? 7. Does mass effect velocity? Why or why not? 8. How are mass, velocity, and projectile motion related? Answer question in workbook

Engineering Design: The Assignment Client: Project SYNCERE Consultants hired engineers from <SCHOOL NAME>’s Project SYNCERE class, to build a model catapult to demonstrate how projectile motion can be useful for the University of Chicago’s new tennis court facilities. Objective: The catapult must launch the object from a set location, so that it lands in the bucket every time. Dimensions: Your catapult must be at least 4.5” X 4.5” X 4.5” and no more than 6.75” X 6.75” X 6.75”

Engineering Design: Test Phase Design/Construction: PS consultants MUST approve your written design before you will be allowed to receive materials Data: Data tables have been provided to you, to assist in your test trials

Things to Consider.. What angle will you use to shoot your projectile? What will create a force to launch the projectile? What is the mass of the object being launched?