Team Members:

Louie McTall

Paul Muskopf

Tom Noble

Shane Reilly

Ben Rissing

Paul Tucker

Former Team Members:

Gavin Duncan

Gavin Jackson

Charlie Safley

Day 1: Science vs. Engineering and Catapult Introduction

Overview: The students will learn the difference between scientists and engineers. They will also learn about the engineering design process and how it differs from scientific experimentation. A basic introduction to catapults as well as catapult history will be presented to familiarize the students with our project.

Teacher Prep Time: 20 min

  • Make copies of Science vs. Engineering Worksheet (W1.1) and Catapult History Handout (H1.1) for all students
  • Prepare the demonstration video
  • Get TV and VCR
  • Prepare the catapult demonstration
  • Read Teacher Manual to understand catapult operation

Objectives:

  • Students will be able to understand the engineering design process
  • Students will compare and contrast this process with scientific experimentation
  • Teach students basic catapult history and build student interest in catapults

Teaching Standards:

Virginia SOLs:

  • PS.1The student will plan and conduct investigations in which

n) an understanding of the nature of science is developed and reinforced

Massachusetts Science and Technology / Engineering Curriculum Framework:

  • 2.1: Identify and explain the steps of the engineering design process, i.e., identify the need or problem, research the problem, develop possible solutions, select the best possible solution(s), construct a prototype, test and evaluate, communicate the solution(s), and redesign.

ITEA’s Standards for Technological Literacy:

  • Standard 7: Students will develop an understanding of the influence of technology on history.
  • Standard 9: Students will develop an understanding of engineering design.

Materials:

  • Science vs. Engineering Worksheet (W1)
  • Catapult History Handout (H1)
  • Operational ETK Catapult
  • Demonstration video

Description of Class:

Science v. Engineering (25 min)

1.T. distributes both worksheet and handout to students. Students will fill in answers as the class progresses

2.T. asks students what they know about scientific experimentation.

  • T. has students write steps on board.

3.T. discusses how scientists use scientific experimentation to explore the world around them

  • Scientist will research and experiment to test a general theory or question and see if it is true or false.

4.T. asks students to individually write 5 words that describe a scientist.

  • T. writes students words on board as they call them out.
  • T. discusses words with class

5.T. asks students “Using what you know about scientific experimentation, what do you think the engineering design process is?” To start them off, T. will draw the first block of the engineering process on the board and say “Instead of starting with a question, engineers start with a design problem.”

  • With student aid, T. completes the engineering design process on the board.

6.T. asks students to individually write 5 words that describe an engineer.

  • T. writes students words on board as they call them out.
  • T. discusses words with class (similarities and differences between the words used for the scientist and the engineer)

7.T. sums up the differences between science and engineering (reference Teacher Manual)

Catapult Introduction (25 min)

8.T. shows demonstration video

9.T. uses video to transition into a brief outline of what the catapult ETK will cover and of the design challenge.

10.T. shows the students the catapult they will be working with and gives a brief demonstration of how it works.

11.T. leads discussion on catapult history using the History Handout (H1.1)

W1.1: Science vs. Engineering Worksheet

Scientific Experimentation The Engineering Design Process

5 Words that Describe a Scientist5 Words that Describe an Engineer

1.1.

2.2.

3.3.

4.4.

5.5.

W1.1: Science vs. Engineering Worksheet (teacher’s copy)

Scientific ExperimentationThe Engineering Design Process

5 Words that Describe a Scientist5 Words that Describe an Engineer

1.1.

2.2.

3.3.

4.4.

5.5.

H1.1: Catapult History Handout

Catapults
Catapults were the first form of field artillery used during battles by the Greeks. They were used as "siege" machines. The word "siege" means the surrounding and blockading of a town or fortress by an army trying to capture it.

The word Catapult comes from the two Greek words "kata" and "pultos". "Kata" means downward and "pultos" refers to a small circular shield carried in battle. Katapultos was then taken to mean "shield piercer".

The Ballista
The first catapults used by the Greeks were based on the bow and arrow but of a much larger size. The "Ballista" was the name given to the first Greek Catapult. It fired spears instead of arrows and its bow worked very differently from a normal bow.

The Ballista worked like the small wooden propeller and rubber band air planes that children play with today.

Top view of a Ballista. A Ballista being set into firing position.

The Trebuchet
It is believed that the Trebuchet originated in China around 300 BC. Its use in Western Europe can be traced to the crusades of the 12th century. There were two types of trebuchets.

  1. The traction trebuchet used people as a power source. The people would haul down the shorter end of the beam which flipped up the longer end. A sling was attached to the longer end of the beam. As the longer end reached its apex, the sling opened releasing a large stone or other object. The traction trebuchet was good for throwing incendiaries and heads.

Traction Trebuchet about to be fired.

  1. The Counterweight Trebuchet replaced the people power with a weight on the short end. The longer end was pulled down, lifting the weighted end. Upon release, the weight pull down the shorter end down and the longer end swung up. A stone was released from the sling at the apex of the swing.

Counterweight Trebuchet prepared to fire.

Day 2: Energy

Overview: Students will gain an appreciation of energy principles, including kinetic and potential energy. They will also examine the basic equations governing energy. The teacher will lead a discussion of the Law of Conservation of Energy and the SI unit system. Students will complete an activity on the subjects of spring constants and potential energy.

Teacher Prep Time: 20 min

  • Make copies of Energy Worksheet (W2.1) and Spring Constant Worksheet (W2.2) for all students
  • Obtain supplies for Spring Constant Experiment
  • A spring scale for each group
  • A ruler for each group
  • Rubber bands of different thickness and sizes for each group

Objectives:

  • Students will be able to understand the both kinetic and potential forms of energy
  • Students will become familiar with the equations governing kinetic and potential energy
  • Students will learn about the Law of Conservation of Energy
  • Students will be able to identify SI units pertaining to the ETK
  • Students will learn how potential and kinetic energy relates to springs and rubber bands.

Teaching Standards:

Virginia SOLs:

  • PS.1The student will plan and conduct investigations in which

b) length, mass, volume, density, temperature, weight, and force are accurately measured and reported using the International System of Units;

c) conversions are made among metric units applying appropriate prefixes;

d) triple beam and electronic balances, thermometers, metric rules, graduated cylinders, and spring scales are used to gather data;

  • PS.5The student will investigate and understand changes in matter and the relationship of these changes to the Law of Conservation of Matter and Energy. Key concepts include

a) physical changes.

  • PS.6The student will investigate and understand states and forms of energy and how energy is transferred and transformed. Key concepts include

a) potential and kinetic energy;

b) mechanical, chemical, and electrical energy; and

c) heat, light, and sound.

  • PS.10The student will investigate and understand scientific principles and technological applications of work, force, and motion. Key concepts include

c) work, force, mechanical advantage, efficiency, and power

  • Math 8.14 The student will

a) describe and represent relations and functions, using tables, graphs, and rules

  • Math 8.17 The student will create and solve problems, using proportions, formulas, and functions.
  • Math 8.18 The student will use the following algebraic terms appropriately: domain, range, independent variable, and dependent variable.

Materials:

  • Every student receives Energy and Spring Constant Worksheets
  • Each group needs:
  • Rubber bands A, B, C, and D
  • Ruler
  • Spring Scale

Description of Class:

Introduction to Energy (25 min)

Note: Students will use the information in 1, 2, 3, and 4 to complete Energy Worksheet (W2.1)

1.T. passes out energy worksheet. Students fill in answers as teacher covers concepts.

2.Forms of Energy:

  • T. states that all forms of energy can be put into one of two main categories. T. writes the two categories on board: Potential & Kinetic.
  • T. has students brainstorm examples of Potential and Kinetic energy.

3.T. discusses Law of conservation of energy:

  • T. states that energy can NOT be created or destroyed, it can only change forms.

оExample: T. lifts a book up into the air and says that it now has potential energy. If T. drops the book the potential energy will be converted into kinetic energy as the book falls. When the book hits the floor, the kinetic energy of the book moving will be converted into sound and heat. T. drops the book.

4.Equations that Govern Energy:

  • T. states that the Potential Energy related to the height of an object is known as gravitational potential energy.
  • T. writes the equation for gravitational potential energy on the board and describes each term.

оPEgravity = Mass x gravity x height

оTo demonstrate T. gets book from before and drops on floor from a height of approximately 6 inches. Then T. drops book on floor from a height of several feet above. T. explains that the book will go faster and make more noise at impact as the height it is dropped from increases. This is because its potential energy increases as height increases.

  • T. talks about springs and how they are one way to store potential energy.
  • T. writes states that Hookes Law allows us to calculate the amount of potential energy contained in a spring, writes the equation on the board, and describes each term.

оHookes Law: K = spring constant

оPEspring = ½ K x (Length2 – Length1)2

оTo demonstrate T. shoots a rubber band at the board, but only pulls the rubber band back an inch or two. T. then shoots a rubber band at the board, pulling the rubber band back as far as possible. T. explains that the rubber band goes faster and farther as the length you pull it back increases. This is because its potential energy increases as length increases.

  • T. states that an object in motion has kinetic energy.
  • T. writes the equation for kinetic energy of motion on the board and describes each term.

оKEmotion = ½ mass x velocity2

оT. explains the transformation of energy in the two previous cases (book and rubber band). When the book is dropped, the PE becomes KE as it falls. Because of the Law of Conservation of Energy, no new energy is created. PE is converted to KE! When the rubber band is shot at the board, the PE becomes KE in the same manner.

5.Spring Constant Activity (25 min)

6.T. divides students into groups.

7.T. passes out spring constant worksheet and materials to each group.

8.T. reminds students and writes on board the conversion between centimeters and meters.

9.T. goes around and makes sure that each group of students completes the activity.

  • See picture below for a more detailed view of the experiment setup
  • It is easier to hold the spring stationary if a bolt is passed through one end of the spring.
  • Measure displacement from the spring scale/spring connection.
  • Make sure to position the spring scale so that you read Newtons.

10.If class period ends before students can complete Activity 2, T. assigns it for homework.

W2.1: Energy Worksheet

(Teacher’s copy)

There are two main categories of energy, potential and kinetic. Write at least 3 examples of each:

Potential (Stored Energy)Kinetic (Objects in Motion)

1. Holding Object in Air1. Moving Car

2. Stretched Rubber band/Spring2. Baseball after being hit

3. Roller Coaster at top of hill3. RollerCoast at bottom of hill

As the teacher goes over the following material, fill in the empty spaces:

The Law ofConservation of Energy says that energy cannot be created or destroyed.

There are several types of energy (you listed six above). We will talk about two specific types of potential energy and one specific type of kinetic energy.

Potential Energy related to the height of an object is called Gravitational Potential Energy.

The equation used to calculate the amount of this energy follows:

PEgravity = Mass x Gravity x Height

Springs are one device used to store potential energy.

The equation used to calculate the amount of this energy follows:

PEspring = ½ K x (Length2 – Length1)2

In this equation K = Spring Constant

Moving objects have Kinetic Energy of Motion.

The equation used to calculate the amount of this energy follows:

KEmotion = ½ Mass x Velocity2

W2.1: Energy Worksheet

There are two main categories of energy, potential and kinetic. Write at least 3 examples of each:

PotentialKinetic

1.1.

2.2.

3.3.

As the teacher goes over the following material, fill in the empty spaces:

The Law ofConservation of Energy says that energy cannot be created or destroyed.

There are several types of energy (you listed six above). We will talk about two specific types of potential energy and one specific type of kinetic energy.

Potential Energy related to the height of an object is called Gravitational Potential Energy.

The equation used to calculate the amount of this energy follows:

PEgravity = Mass x Gravity x Height

Springs are one device used to store potential energy.

The equation used to calculate the amount of this energy follows:

PEspring = ½ K x (Length2 – Length1)2

In this equation K = Spring Constant

Moving objects have Kinetic Energy of Motion.

The equation used to calculate the amount of this energy follows:

KEmotion = ½ Mass x Velocity2

W2.2: Spring Constant Worksheet

Activity 1: We will determine the spring constants (K) of different springs.

Procedure:

1)Attach one end of the spring to the spring scale and the other end around a bolt. Position the ruler so that 0 is at the spring scale – spring connection.

2)Stretch the spring a little bit to get rid of slack.

3)Write down length (Length 1) and reading on the scale (Force 1) in the chart below.

4)Stretch spring 5 more centimeters and record length (Length 2) and spring scale reading (Force 2)

(Remember 100 centimeters = 1 meter).

5)Repeat procedure for each of the different springs (B, C, and D).

6)Calculate spring constant (K) using the rearranged equation from the energy worksheet:

K = (Force 2 – Force 1)___

(Length 2 - Length 1)

Spring / Length 1 (m) / Force 1 (N) / Length 2 (m) / Force 2 (N) / K (N/m)

A

B
C
D

Activity 2: We will determine how much potential energy is stored in each spring if we stretch it 15 cm? 30 cm?

Hints: Don’t forget about the units! 1 joule = 1 N m

Use the appropriate K value from the chart you just completed

PEspring = ½ K x (Length 2 – Length 1)2

Spring / K (N/m)
(from above) / PE at (Length 2 – Length 1) = 15 cm (0.15 m) / PE at (Length 2 – Length 1) = 30 cm (0.3 m)
A
B
C
D

Day 3: Simple Machine (Levers) & Projectile Motion

Overview: Students will gain knowledge of simple machines, specifically levers and how they apply to catapults. Students will gain an interactive, conceptual knowledge of projectile motion.

Teacher Prep Time: 20 min

  • T. must set up three catapults for the lever demonstration. The fulcrum of each catapult arm will be at a different point, one in the middle, one on the extreme right, and one on the extreme left. Each lever has a weight on the right end (see diagrams below).
  • T. make enough copies of Simple Machine Handout and Lever Worksheet for the entire class

Objectives:

  • Students will recognize the 6 types of simple machines.
  • Students will understand the 3 classes of levers.
  • Students will understand the relationship f1d1 = f2d2
  • Students will see real life applications of projectile motion.
  • Students will gain experience with equations and substitution.

Teaching Standards:

Virginia SOLs:

  • PS.10The student will investigate and understand scientific principles and technological applications of work, force, and motion. Key concepts include

a) speed, velocity, and acceleration;

c) work, force, mechanical advantage, efficiency, and power; and

d) applications (simple machines, compound machines, powered vehicles, rockets, and restraining devices).

  • Math 8.17 The student will create and solve problems, using proportions, formulas, and functions.
  • Math 8.18 The student will use the following algebraic terms appropriately: domain, range, independent variable, and dependent variable.

Materials:

  • Simple Machine Worksheet (W3.1) for each student
  • Levers Worksheet (W3.2) for each student
  • Styrofoam (5” diameter) ball
  • 3 Catapults and 3 equal weights
  • 1 fully prepared Catapult

Description of Class:

Simple machines and Levers (25 min)

1.T. asks students what they think simple machines are

2.T. explains that simple machines are tools used to make work easier.

3.T. describes the 6 types: inclined plane, wedge, screw, lever, wheel and axle, pulley. Students fill in worksheet (W3.1) as teacher goes over material.

4.T. talks about how simple machines are all around us. T. asks students to point out simple machines just within the classroom. Then T. asks students to identify simple machines they use at home every day.