Priinciples of Engineering 2022

2

CIJE-Tech High School CENTER FOR
INITIATIVES IN
Principles of JEWISH
Engineering EDUCATION

If you can't explain it simply, you don't
understand well enough.
- Albert Einstein

Center for Initiatives in Jewish Education

President Jason Cury
Senior Vice President Amy Z. Amiel
Vice President, Education Barbara Gereboff, Ph.D
Vice President, Professional Development Faigy Ravitz
Director, Curriculum Development Adam Jerozolim, M.E.
Coordinator, Innovational Programs Orly Nadler, M.A.

CIJE STEM Specialists: Yafa Lamm
Katherine Owuor, Ph,D.
Dewain Clark, M.A. Joseph Saltzman
Christopher Auger-Dominguez David Seay, M.A.
Kate Van Dellen, M.S. Rabbi Heshy Wieder, M.A.
Teresa Doan
Robert Jones

© 2022 All Copyrights belong to Center for Initiatives in Jewish Education. No part of this book
may be copied, duplicated, recorded, translated or stored in any database of any kind or by any
other means. Any use of the material contained in this book is prohibited unless it is with the
express permission of the publishers and authors.

Center for Initiatives in Jewish Education
148 39th Street, Suite A311, Brooklyn, NY, 11232
[email protected]
212-757-1500 Phone
212-757-1565 Fax

This program was produced with the generous support of the Center for Initiatives in Jewish
Education (CIJE) as part of its ongoing quest to achieve excellence in education.

The Center for Initiatives in Jewish Education
(CIJE)

The Center for Initiatives in Jewish Education (CIJE) strengthens and enriches the quality of
education in Jewish schools throughout the United States. CIJE is investing in our nation's future
by providing beneficiary schools with cutting-edge technology, engaging curricula, and vital
support so that students can acquire the skills they need to excel in our global society.
Currently, CIJE has more than 225 beneficiary schools across the United States and programs
which span grades K-12. CIJE's innovative programs are paving the way for the achievement
and success of tomorrow's leaders and thinkers.

CIJE-TECH STEM PROGRAM: AN OVERVIEW

More than ten years ago, the Center for Initiatives in Jewish Education began the
implementation of various STEM programs in elementary Jewish schools. The success of these
programs brought about the initiation of the CIJE-Tech Principles in Engineering and Applied
Engineering programs.
Goals:
The CIJE STEM education programs:

• Provide a challenging and rigorous program of study focusing on the application of STEM
subjects.

• Offer courses and pathways for preparation in STEM fields and occupations.
• Bridge and connects in-school and out-of-school learning opportunities.
• Provide opportunities for student exploration of STEM related fields and careers.
• Prepare students for successful college and university STEM education.

To increase STEM learning, the CIJE-Tech programs include activities that improve student and
teacher content knowledge and teacher pedagogical skills. Innovative strategies are used,
including small group collaborative work and the use of hands-on activities and experiments to
promote inquiry and curiosity. Learning is connected to the real world through an emphasis on
the application of STEM subjects to everyday life, employment, and the surrounding
environment.
The CIJE high school programs were approved as "d" Laboratory Science Courses by the
University of California in 2015. The second-year course is approved at the more
challenging honors level.



TABLE OF CONTENTS

UNIT 1: ENGINEERING AND THE DESIGN PROCESS ........... 7 WORK SHEET: SENSORS .........................................................142
COMMON SENSORS AND ACTUATORS.......................................148
WORKSHEET: ENGINEERING DESIGN ............................................... 10
CHALLENGE: DESIGN A SHOE ......................................................... 17 UNIT 12: SENSORS IN CIRCUITS ................................ 149

UNIT 2: THE SYSTEM...................................................... 21 WORK SHEET: SENSORS IN A VOLTAGE DIVIDER..........................153

LAB: DIGITAL MEDICAL THERMOMETER EXPERIMENT ......................... 25 UNIT 13: THE CAPSTONE PROJECT......................... 157
TOYS IN MOTION PART 1: MECHANICAL MOTION ............................. 29
UNIT 14: FLOW CONTROL.......................................... 179
UNIT 3: INTRODUCTION TO CAPSTONE PROJECTS .......... 31
LAB: IF/ELSE STATEMENTS......................................................186
WORKSHEET: IDENTIFYING A PROBLEM............................................ 34 LAB: FLOW CONTROL ............................................................193
LAB: TIMING .......................................................................196
UNIT 4: ELECTRICITY AND OHM’S LAW .................. 35 LAB: PHOTOGATE .................................................................197

WORKSHEET: ELECTRICITY AND CURRENT ........................................ 46 UNIT 15: BUTTONS, TRANSISTORS & ANALOGWRITE. 199
TOYS IN MOTION PART 2: ELECTRIC CIRCUIT .................................... 50
LAB: ANALOG WRITE AND RGB LED'S .....................................203

LAB: ANALOG WRITE, TRANSISTORS AND DC MOTORS ........ 205

UNIT 5: USING THE MULTIMETER .......................... 53 LAB: BUTTONS AND DIGITAL READ ..................................210
UNIT 16: SERVO MOTORS & ULTRASONIC SENSORS .. 211
LAB: USING THE MULTIMETER – VOLTAGE ....................................... 55
LAB: USING THE MULTIMETER – RESISTANCE.................................... 58
LAB: USING THE MULTIMETER – CURRENT ....................................... 61

UNIT 6: OHM’S LAW ............................................... 65 LAB: ULTRASONIC DISTANCE SENSOR ...............................213

WORKSHEET: SERIES CIRCUITS ....................................................... 69 LAB: SERVO MOTOR .....................................................215
LAB: CAPACITANCE ...................................................................... 73 LAB: COMBINING CODES - AUTO BATTER..................................218

UNIT 7: ARDUINO MICROCONTROLLERS ........................ 75 UNIT 17: DATA TYPES, ARITHMETIC & FUNCTIONS .. 219

LAB: INTRODUCTION – THE ARDUINO MICROCONTROLLER .................. 82 LAB: DATA TYPES .................................................................223
LAB: ARITHMETIC .................................................................231
LAB: SECTIONS 1-4 - BASIC STRUCTURE AND BLINK ................... 88 LAB: ARDUINO FUNCTIONS.....................................................236

LAB: TRAFFIC LIGHT ..................................................................... 92 UNIT 18: ENTREPRENEURSHIP................................... 237

WORKSHEET: DATASHEETS............................................................ 93 WORKSHEET: BUSINESS PLAN .................................................243
WORKSHEET: ECONOMICS TERMS ...........................................246
UNIT 8: ARDUINO CODING TOOLS ................................. 97 WORKSHEET: MAKING A PROFIT .............................................249
LAB: WHAT AFFECTS PRICING? ...............................................251
LAB: SECTION 1 - DEBUGGING ..................................................... 101
LAB: SECTION 2 - GLOBAL VARIABLES............................................ 106 APPENDIX A – BINARY..................................................... 253

UNIT 9: ADVANCED CIRCUITS...................................... 107 LAB: SECTION 16 - BINARY.....................................................256

WORKSHEET: BREADBOARDS, SERIES AND PARALLEL ........................ 115 APPENDIX B – UNIT CONVERSION AND DIMENSIONS. 257
LAB: ADVANCED CIRCUITS (BREADBOARD, SERIES, PARALLEL)............ 116
WORK SHEET – UNIT CONVERSION ..........................................263
UNIT 10: VOLTAGE DIVIDERS AND ANALOGREAD .. 121
APPENDIX C – LCD DISPLAY ............................................. 267

WORK SHEET: VOLTAGE DIVIDER ......................................... 125 LAB: LCD DISPLAY .......................................................268
LAB: ANALOG DATA AND SERIAL MONITOR .................................... 131 INSTALLING LIBRARIES ...........................................................268
LAB: SENSORS IN A CIRCUIT ......................................................... 134
APPENDIX D – RF TRANSMITTER...................................... 270
UNIT 11: INTRODUCTION TO SENSORS .......................... 137
LAB: RF TRANSMITTER ..........................................................271

“Scientists investigate that which
already is; Engineers create that
which has never been.'”

- Albert Einstein

Unit 1:
Engineering
and The
Design Process

Principles of Engineering

Preface

The design process is a system of steps developed to systematically solve complex engineering
problems.

Unit Sections:

➢ What is Engineering
➢ The Design Process
➢ Worksheet: Design Process

Learning Objectives

After completion of this unit students will be able to:
➢ Become familiar with the Engineering Design Process
➢ Understand the different stages of the Design Process
➢ Understand how to incorporate the various stages in solving complex engineering
problems
➢ Understand what parts of the Design Process are applicable to various stages of a
complete engineering project

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Principles of Engineering

What is engineering?

Engineering is the application of scientific and mathematical principles to design, manufacture,
and operate efficient and economical structures, machines, processes, and systems that solve
real world challenges and support the quality of life. Engineering is often broadly defined within
the electrical, mechanical and chemical disciplines with focuses on more specific applications
like robotics, computer, architectural, civil, aerospace, biomedical and agricultural.
Engineers are problem solvers, organizers, communicators, calculators and designers. They are
capable of clearly defining a problem and its relevant constraints (such as time, cost, etc.) and
providing a simple solution. There are many team roles that require different skills and tasks. A
senior engineer, for example, will usually perform less technical work (calculations and designs)
but instead focus on managing a project or team of engineers.

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Principles of Engineering

Worksheet: Engineering Design

Let’s consider some innovations in the context of their design, and the problem they aim to
solve. Check out these gadgets from Dreamfarm:

Consider: what problem do you think the “Supoon” solves? How does it benefit the user? When
you rest a spoon on a surface, the contents of the spoon don’t get the surface dirty; like stirring
a pot of soup on the stove and then needing to put the spoon down. The user benefits because
they don’t have to find a place to rest their spoon. Another benefit is that they don’t have to
dirty both a spoon and a spoon rest, cutting down on the amount of dishes needed to be done.
If the user doesn’t need a spoon rest, then they also don’t need the space to store it and some
users will enjoy the look of a nice clean counter. Users also don’t have to take the extra step to
clean the counter after a spoon touches the surface. There could be even more uses for a user
with physical impairments, such as only having one functioning arm/hand.

Now identify the problem and the benefits for the user of each of the other devices:

Tool What problem does it solve? How does this benefit the user?
Identify the unique and/or specific users

Chopula

Clongs
10 Unit 1: Engineering and The Design Process | CIJE

Garject Principles of Engineering
Levons
Scizza CIJE | Unit 1: Engineering and The Design Process 11
Smood
Tapi
Teafu

Principles of Engineering

The Design Process

If you were an alien observer that came across a photo of this
human, explain that blue thing on their face. Is it fulfilling its
purpose? Did the design fail to solve the problem? What about
those black shiny things above their nose? What is their purpose?
The practice of engineering is to design and build for a need, for a
purpose and for a user. To help find a solution based on the
constraints of that problem there is a process called the Design
Process that guides the engineer towards an effective solution.
As an engineer, you will be using the Design Process to solve challenges throughout this course,
as well as designing and building your own solution to a real world problem.

The Design Iceberg

Often in design, there is only a superficial evaluation of the
problem and the need. Meanwhile, there is a whole host of
parameters that lurk under the surface. Beware of:
• Only focusing on the “obvious” problem and solution
• Tendency to seek a highly technical solution
• Emphasis on the solution rather than the problem
• An inefficient, costly design
• Not addressing the needs and abilities of the end user

The Design Process provides a pathway to a solution to a problem or need. It is a method to
find an effective solution to a given problem for a user or set of users. The engineering design
process is a series of steps that engineers follow to come up with a solution to a problem. Often
the solution involves designing a product (like a machine or computer code) that meets certain
criteria and/or accomplishes a certain task. While the words may vary with the source, the
Design Process boils down to these common steps from inception to production: Empathize,
Define, Brainstorm, Build and Test.

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Principles of Engineering

A. Empathize

This is the opportunity to get to know the
problem intimately. The engineer
researches the problem from all angles,
learning about the science of the problem
as well as the individual(s) involved. The
goal here is to understand, to empathize,
with the user.

Much like a detective, there are many ways

to collect information about a problem but Can you make assumptions about this person based

they all derive around asking questions: on the photo?

Who, What, Why, Where, When. Who does

this problem involve? What are the parameters and conditions in which this occurs? What are

the scientific facts of the problem? Why does this happen and why is it important to solve?

Where does this problem happen? At school? At home? And when? At night? Daily?

See the world through THEIR eyes

• Build empathy for users
• Users have direct experience with the problem
• Better design FOR the user
• Be inspired by the need for a solution

Example: A school would like to lower their carbon footprint while becoming more electrically
independent. Where is this community? How many people? What are the cultural, economic,
political constraints to consider?

How to research:

• Survey users and those who experience the problem

• Ask questions (Who, What, Why, Where, When)

• Observe the problem in action

• Look at existing solutions

• Read about the science of the parameters of the problem

B. Define

You might have started with an idea of the problem, but after
researching and getting to know all of the issues, state the problem
again in the context of the user, the needs, and the research. What
are the parameters of this problem? Is the problem what you
expected before you did your research?

Example: A school wants to generate and use their own renewable, scalable energy on campus.

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Principles of Engineering

C. Brainstorm

Consider your research about the problem, the user and need. Either on your own or with a team,
take some time to brainstorm ideas. Brainstorming, as the name implies, is thinking of many
creative solutions to the problem, ranging from the practically to some that seem at first crazy or
even impossible. Let your brain do what it does best: create ideas. Here are some guidelines for
brainstorming:

IDEA IDEA IDEA

solution solution solution

IDEA IDEA IDEA

solution feature feature

1. Create a (safe) space and (dedicated) time to individually or with a team to brainstorm by:

• Deferring judgement or criticism, including non-verbal. Be positive and build on the
ideas of others. Use the phrase: “How Might We...”

• Being inclusive of everyone’s ideas, no matter how “crazy”. This isn’t the time to be
practical just yet. You never know what you might dream up.

2. Collect a list of ideas to meet the needs and benefits of the solution

• Consider different potential solutions to the same problem, not just different features of
the same solution.

• Write / record the ideas as they come: Some use a whiteboard, maybe post-it notes or
simply a piece of paper. Everyone can contribute or have a scribe to record the process

• Embrace out-of-the-box notions: Encourage weird, wacky, and wild ideas and

• Aim for quantity: The more you consider, the more new ideas will form

• Be visual: Sketch ideas out, find images
3. Select an idea or a combination of features that you will build

• Respectfully review the range of ideas in the context of “What if… “

• Select features that address the need and benefits for the user you’ve identified

• Is the scope (size, number of features) achievable with the budget, time and materials?

Example: renewable energy sources: solar panels, wind turbine, tidal turbine, fusion.
Features of solar panel solution: solar farm (multiple panels), trackable, snow clearing
robots (solar may not work well in the winter in Alaska)
Features of tidal power: underwater turbine that collects power from the movement of
water during the rise and fall of the tide, fish friendly, stores power in the form of
hydrogen without the need of intrusive power line infrastructure.

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Principles of Engineering

D. Build

Once the idea has been parsed, it’s time to
build. Often a prototype is built first before the
final version to test out the design to see how
pieces will fit together and how well it manifests
the benefits and features you’ve defined in the
previous steps.

• Plan: Plan the build with hand drawn or
computer assisted design (CAD) mindful of
measurements and scale. The code as well
should be sketched out with a flow chart at
least, delineating inputs, outputs and
processed information. Electronics can be
drawn out in a wiring diagram.

• Consider the entire package: how the pieces
will fit together, how electronics will be housed, where buttons, switches and other
interactions will be placed, how it will physically fulfill its design criteria for its purpose,
what sensors and data needs to be considered for the final product.

• Find solutions quickly: Don’t get bogged down on any one problem. Push through and find
solutions, get help when needed and you may have to go back a couple steps and review
your problem statement and check your research.

• Prototypes: “Quick” prototype
build: Initial prototypes are often
built “quickly”, sometimes at
smaller scales, with readily
available materials and
components to work through
issues of space as well as
function. 3D printing is an
example. It is an accessible and
quick way to build and iterate
but in final production it may not
be practical.

Iterative: This is an iterative process,
meaning you may build and rebuild
(whole or parts) as you learn what
works and what doesn’t.

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Principles of Engineering

E. Test

Once the gadget or machine is built, it should be tested in the situation for which it was designed.
Example: Install the wind turbines in the Alaskan community and test for 6 months.

Assess

A part of the testing process, in fact throughout the Design process, we should assess the design
in the perspective of the problem, need and the user. This is the opportunity to evaluate the
design both as a team and to get feedback from users.
Evaluate how it works, how users interact with it. Does it solve the problem for which it was
designed? Does it meet the needs of the user? Does it need improvement? Are the components
and program working? How is the UX (User Experience: how the user interacts with the gadget)?
Is it usable? Meaning: can the people for which it is designed easily understand and manipulate
the product? Success might come early but often you may have to go back a couple steps based
on new knowledge, essentially new research, and alter design aspects to fulfill the need.
Example: What are the environmental impacts of the turbine? Is it producing enough energy?
Is it within the cost to repeat and build multiple units?
In the Design Process, we assess the successes and failures from each step and adjust next steps
accordingly or step back and do again.

Iteration

Each step is crucial in providing a successful and useful final product. While each step feeds the
next, the process can be recursive and involve taking a step back depending on what was learned
in a particular step. Particularly in the Build stage, you may find that a design choice just doesn’t
work and you will need to re-evaluate that decision, measurement, sensor choice, placement of
elements, etc. and rebuild a new version.

16 Unit 1: Engineering and The Design Process | CIJE

Principles of Engineering

Challenge: Design a Shoe

In the previous exercise, you got to know your shoes. What your shoes experience gives you a
perspective on what affects them, harms them, wears them down as well as what benefits or
strengths they have in their design. Now you will take that approach (and knowledge) to design
a shoe for your lab partner. The following worksheets will take you step by step through the
Design Process. Don’t dally, don’t hesitate, get into it and work through the entire process. You
should be able to have something finished by the end of class. Your teacher will keep you on
strict timing. This isn’t to stress you out, it is to work through the entire Design Process with a
loose creative energy that will give you both a perspective on the entire process as well as the
value of thinking creatively to solve problems.

1. Draw (3 min): Sketch your ideal shoe

2. Interview (8 min: 2 sessions of 4 minutes each): Design something useful and meaningful
for your partner. Start by gaining empathy. Notes from your first interviews:

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Principles of Engineering

3. Dig Deeper (6 min: 2 sessions of 3 minutes each): Interview another 2 students with more
pointed and directed questions and observations. Notes from your second interviews:

4. Reframe the problem (Define) and capture findings (3min): Goals and wishes (What is
your partner trying to achieve?

________________________________________________________________________

________________________________________________________________________

________________________________________________________________________

________________________________________________________________________

________________________________________________________________________
5. Insights (New learnings about your partner’s feelings and motivations. What’s something

you see about your partner’s experience that maybe they don’t see?

________________________________________________________________________

________________________________________________________________________

________________________________________________________________________
6. Take a stand with a point of view (3 min):

____________________ needs a way to _______________________________________

Name user’s need

because / but / surprisingly __________________________________________________
insight

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Principles of Engineering

7. Ideate: generate alternatives to test. Sketch at least 3 radical ways to meet your user’s
needs (5 min)

8. Share your solutions and capture feedback (10min: 2 sessions x 5 minutes each)
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
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Principles of Engineering

9. Iterate based on feedback. Sketch your idea, note details if necessary.

10. Build and test. Build your solution. Make something you can interact with using a shoe
and some masking tape and paper. Share your solution and get feedback. (8 min: 2
session x 4 minutes each)

What worked What could be improved

Questions Ideas

20 Unit 1: Engineering and The Design Process | CIJE

Unit 2: The
System

Principles of Engineering

Preface

This unit addresses the subject of engineering in general and a central concept in engineering –
the system. In this unit, you will analyze how a biomedical device – a thermometer – works and
link it to the system.

Unit Sections:

➢ A System
➢ Matching the Function of a System to its Purpose
➢ Analyzing a Digital Thermometer as a System
➢ Lab: Digital Medical Thermometer Experiment
➢ Mechanical Systems

Learning Objectives

After completion of this unit students will be able to
➢ Define the concept of a system
➢ Learn about the general structure of a system and analyze systems according to this
structure
➢ Learn about the pedometer and the thermometer
➢ Learn about the features of technological systems including the range of measurement
➢ Observe how things are put together and fit together
➢ Explain reverse engineering
➢ Describe the relationship of the individual components with each other and within the
whole system

22 Unit 2: The System | CIJE

Principles of Engineering

A System

A collection of objects that function interdependently to achieve a defined goal.
In general, we describe the system as having an entry (input) and an exit (output). The output
should cater to the need or goal for which the system exists. The following block diagram shows
a structure of a system

The arrow indicates a flow of input or output. A system can have a number of inputs and outputs,
and a number of processes can take place within it.

Feedback

When the output values are used to alter or influence the input values, we call this a feedback
loop.

CIJE | Unit 2: The System 23

Principles of Engineering

Computer Systems

Below is a block diagram of a computer system:

Input Process Outputs

• User commands • Calculations • Pictures
• Mouse • Creation of images and sounds • Sounds
• Keyboard • Printouts

Arduino as a System

Below is a block diagram of an Arduino Microcontroller system:

Input Process Outputs

• Light/Dark Sensor • if statement • LEDs
• Temperature Sensor • while loops • Motors
• Sound Sensor • for loops • Buzzers
• Tilit Sensor • 555 Timer • Relays
• Button • arithimitc • Serial print
• Switch

Matching the Function of a System to its Purpose

There is a close link between the functionality and use of the system and its purpose. Think of a
computer keyboard, for example. Why are the keys a certain size? Why is the mouse shaped as
it is? Why is it possible to run different programs simultaneously? All these are designed to enable
us to use the system comfortably and for the system to fulfill its purpose in the most effective
manner.

For example, a digital medical thermometer, used for measuring a person’s body temperature,
will be designed to measure temperatures that are close to body temperature 35.6°C
(approximately 98°F) and generally will not be able to measure temperatures lower than 30°C or
higher than 45°C. Similarly, its degree of precision
will be a tenth of a degree since we don’t need a
more accurate measurement (e.g. between 36.66°C
to 36.67°C). Also, the device will be adjusted to fit
the area of the body where the temperature will be
measured and to the manner of which it is being
measured. For example, it will be suitable for
placement either on a certain area on the skin
surface or inside the body.

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Principles of Engineering

Lab: Digital Medical Thermometer Experiment

Purpose

The goal of the lab is to study and discover the operating envelopes of various thermometers,
and to determine what operating conditions can be used to drive engineering design. Students
will try and determine what conditions, specifically, were used in determining the operating
ranges and physical designs of a human medical thermometer and a chemistry beaker
thermometer.

This activity contains three parts:

➢ Conduct the experiment
➢ Analyze the findings and increase your understanding of the system concept.
➢ Write conclusions about the properties of the system.

Safety

In this experiment, you will be working with hot water. Water is a substance with high heat
capacity, so hot water is dangerous and may cause severe scalding. Therefore, you should wear
suitable gloves while handling the water.

Part 1 – Procedure

Required Apparatus:
• 1L vessel
• 0.5L of tap water
• 0.5L of hot water above 50°C
• Digital medical thermometer
• Non-medical thermometer (i.e. - cooking, chemistry, outdoor, etc.)
• 200ml measuring flask

Procedure
1. Pour 100ml of tap water in to the empty 1L vessel.

2. Measure and record the temperature of the hot water ______________ and the cold
water ______________. Which thermometer did you use? Why? _________________
________________________________________________________________________

3. Measure and record on the table below the temperature of the tap water. Use both
thermometers.

4. Add 30ml of hot water to the tap water.
5. Stir the water.
6. Repeat questions 3-5 until the hot water runs out. Complete the following table.

CIJE | Unit 2: The System 25

Principles of Engineering

Measurement Total Amount of Water temperature Water temperature
number amount of hot water according to according to the
water (ml) medical
(ml) other thermometer
thermometer (°C) (°C)
0
1 100 30
2 130
3 160
4 190
5 220
6 250
7 280
8 310
9 340
10 370
11 400

7. In your opinion, what are the physical differences between the two thermometers? What
are the reasons for this?

Part 2 – Analysis of the Digital Medical Thermometer System

8. Take the system components apart and write down the parts you identify. Write down
the function of each part, in your opinion.
Part Function

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Principles of Engineering

9. Identify and write down the following elements of the system:
Inputs: _________________________________________________
Process: _________________________________________________
Outputs: _________________________________________________

10. Draw the block diagram of the system:

11. In your opinion, how does the system work?
________________________________________________________________________
________________________________________________________________________

12. What is the measurement range of the system?
________________________________________________________________________

13. In your opinion, what is the reason for this range?
________________________________________________________________________
________________________________________________________________________

Part 3 – Conclusion
14. How does the system's design match its purpose?
________________________________________________________________________
________________________________________________________________________
15. Suggest a possible change to the system. Explain how the change that you suggest will
improve the system (i.e. - will provide a better solution, will answer another need, will
save costs, etc.)
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
CIJE | Unit 2: The System 27

Principles of Engineering

Mechanical Systems

A mechanical system manages power to accomplish a task that involves forces and movement.

The relationship of individual components and how they physically fit together is important.

Much like how in an electrical system of input and process produces an output, the

combination of form with power yields action. = Movement

Form Power

A combination of pulleys, belts, gears, or cams provide a transfer of the power to create
movement. Consider, for a moment, how a doorknob opens a door: Your hand, providing the
source of power, turns the knob which turns a cam inside that slides the latch away from the
door frame.

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Principles of Engineering

Toys in Motion Part 1: Mechanical Motion

In this lab students will have an opportunity to explore how mechanical systems are put
together to create motion.

What is the purpose of toys?

As an engineer, to build and design a toy, like any product, it is important to keep in mind for
what and for whom they are created. Did you ever have a toy? What was your favorite? What
did it do and what purpose did it serve? To entertain? To educate? And is there any age that
someone can use a toy? Take a moment to discuss with your classmates what your favorite toy
was and why you liked it.

Toys that move.

Let’s say you’re designing a toy that moves on its own. Let’s do some brainstorming on toys you
know that move. Do they walk? Roll? Fly? How do they do this motion? What powers the
motion? What are they made of?
One way to find out is to examine a toy to see what it’s made of and how it works. We call the
process of taking apart a product to study its components and figure out how it works, reverse
engineering. Reverse engineering is learning from the existing design and applying it to a new
or improved design. People use reverse engineering for software, architectural structures,
appliances, and processes.

1. Follow the instructions to build your toy.
2. Once it is put together, observe how your toy moves. Describe the motion and parts.

Does it wiggle? Roll? Walk? Etc.
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
3. Sketch the toy and identify the components:

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Principles of Engineering

4. Sketch the moving mechanical portion of the toy, including the source of motion
(motor, spring, etc.) and all the linkages, gears, levers, cams, etc. involved in transmitting
motion.

5. Considering the purpose of a “toy”, does this toy fulfil its purpose? Why or why not?
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________

6. Develop and build a new toy using the kit provided. The toy should have moving parts,
including gears, linkages, wheels, etc. Share your toy with the class and describe its
movement. Observe how they are different than the other groups.

30 Unit 2: The System | CIJE

Unit 3:
Introduction
to Capstone
Projects

Principles of Engineering

Preface

The objective of the Capstone Project is to identify a problem and design engineer an innovative
solution to the problem or improve upon an existing solution. This unit serves to begin the
process of getting students to think like a design engineer and recognize problems and design
solutions. A more comprehensive unit on the Capstone Project may be found in Unit 14.

Unit Sections

➢ The Capstone Project
➢ Identifying Problems
➢ Worksheet: Identifying a Problem

Learning Objectives

After completion of this unit you will be able to:
➢ Describe the objective of the Capstone Project
➢ Recognize and identify problems
➢ Describe the process of creating a solution to a problem which culminates with a
Capstone Project

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The Capstone Project

The objective of the Capstone Project is to identify a problem and design and engineer an
innovative solution to the problem or improve upon an existing solution. This requires the
building of a physical device (the solution to the problem) that includes embedded
programming (coding) and electronics. The Capstone Project phase begins mid-way through
the course in Unit 7 and will involve teams of two-three students. The final project will be
presented at the Center for Initiatives Young Engineers Conference that is held in the spring.
This conference is attended by other schools participating in the CIJE program.

Identifying Problems

The first step in the Capstone Project is to identify a problem that needs a solution. This forms
the basis of the project idea. It is never too early to begin the process of identifying a problem.
If you begin to think of problems now, by the time you reach the Capstone Phase of the course
you may have considered a number of problems that might be suitable for design engineering
a solution.

Where will the identification of a problem come from? Inventors begin inventing the moment
they wake up in the morning. They see the world as a series of problems that need to be solved
with the inventions. They make no assumptions and believe that all problems can be solved or
existing solutions improved upon. Sometimes they stumble on an invention and stop and
consider what potential uses the invention can provide.

“The greatest invention to the world is the mind of a child”, remarked Thomas Edison.

Thomas Edison is referring to the fact that children are not conditioned by the assumption that
they cannot improve the world by inventing, so they are born inventors with an inherent
curiosity.

Where does an invention begin? It begins with the observation of the world around you. Look
for a need and also ask the question, “can something be improved?” Consider the following
examples:

Drip Irrigation The Post-it Note

In Israel in the 1930’s a water engineer called The post-it note was
Simcha Blass was visiting a friend at his farm invented in 1968 by Dr.
and noticed a line of trees where one tree Spencer Silver a scientist
stood out in that it was greener and taller. On from 3M. He was
further investigation, he noticed that there attempting to develop a
was a small leak in a water line. This small very strong adhesive. However, he
leak had generated enough water to create a accidentally invented a low-tack adhesive. In
vast improvement in growth of the tree. 1974 a colleague who attended a seminar
From this observation, the drip irrigation given by Dr. Silver considered using them as
industry began, a major industry that is at the a bookmark. The idea of using the notes as
forefront of global water conservation. bookmarks took off and post-it notes became
a household name. An interesting fact is that
they were originally all yellow because the
lab only had yellow paper.

CIJE | Unit 3: Introduction to Capstone Projects 33

The greatest inventions are always related to everyday life. By using the
power of their senses, inventors can find problems that need to be fixed.
Once they have identified a problem, and then a solution they have an
“aha” moment! Often every day inventions came from a person who
looked at things with an open mind to see if they could be improved. Over
the next few months, use all your five senses to observe and monitor the
world to look for problems.

Worksheet: Identifying a Problem

Making the Observation

Working in teams, observe your surroundings and identify problems or difficulties. Record
them in the table below. Do not assume there are already solutions. Innovation is often the
improvement of an existing solution. Brainstorm solutions to the problem and complete the
table below. Choose the best solution to a problem and present this to the class. Include a
drawing of what the solution should look like.

Description of the Description of a solution to the problem, or improvement of an
Problem existing solution to a problem. Include a sketch of your solution

Solution 1 Solution 2

Unit 4:
Electricity and
Ohm’s Law

Principles of Engineering

Preface

Electric circuits are the main component in advanced technological systems. In this unit we will
learn the beginnings of how electricity works and get to know about the units used to measure
electricity. We will learn about the relationship between these units and use this to analyze
electronic circuits. We will then learn how to measure them. In the next unit we will apply this
theoretical knowledge to building practical electric circuits. Later in the course we will elaborate
on electric circuits and learn how to connect them to a processing system.

Unit Sections:

➢ Introduction to the Physical Structure of Atoms
➢ Electrical Units
➢ Electrical Charge
➢ Electrical Current
➢ Voltage
➢ Resistance
➢ Connecting Resistors in a Series
➢ Ohm’s Law
➢ Measuring Voltage and Current
➢ Worksheet: Introduction to Electricity

Learning Objectives:

After completion of this unit students will be able to:
➢ Describe the physical concepts of charge, resistance, current, and voltage
➢ Compute values using Ohm’s law
➢ Measure resistance, voltage and current

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Electrons

All matter is composed of atoms. Each atom is itself composed of three types of particles:
protons, neutrons and electrons. The protons and neutrons are at the center of the nucleus, with
the electrons orbiting further away. For a stable atom, the number of electrons is equal to the
number of protons.

Electrical Charge

Electrical charge is an electrical property of particles and matter. Protons are positively charged,
electrons are negatively charged, and the two attract each other. If you take one electron away
from an atom, the atom has a charge of +1 because there is one more proton than electrons, and
if you have an extra electron it becomes -1 since there is an extra electron. The smallest charge
you can achieve is with one electron.
Under ordinary circumstances, atoms have a neutral charge, which doesn't mean they have no
charges, but that they contain an equal number of positive and negative charges. At the energy
levels of our daily lives, we cannot break protons free from their nuclei.
The symbol of charge is the letter Q. On our scale, a single electron is so tiny that we would never
count just one, so the unit of charge Coulomb (named after Charles-Augustin de Coulomb and
marked by the symbol C) is used. 1 Coulomb is equal to 6.24150965 × 1018 electrons.
Neutrons do not have any charge, while electrons and protons are electrically charged. An
electron and proton have an equal “amount” of charge, but each has an opposite charge symbol.
It is customary to say that an electron charge is negative and a proton charge is positive.
Electrical forces act upon charges. Opposite charges attract each other while similar charges repel
each other. In other words, two positive charges repel each other, two negative charges repel
each other and two substances of which one is positive and the other negative attract each other.
The intensity of the force depends on the size of the charges (large charges exert a stronger force
between them) and their distance (the greater the distance the weaker the force).
If we separate the electrons from the protons, there will be a force pulling them back together.
Whenever we have a force of attraction, there is energy that can be used. The chemical reaction
in a battery separates the electrons from the protons. Conductive pathway provides a way for
electrons and protons to get back together. We can design the pathways to go through motors
and lightbulbs so that they spin and light up when electrons pass through them.

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When a battery is fully “charged” all of the electrons have been removed from their atoms and
are separated with an impermeable wall. The only way for the electrons to reach the protons
they are attracted to is by going through the circuit. When all the electrons have passed through,
and reunited with their protons, the battery is “dead” and has no more potential energy.

Electrical Current

Current is the flow of electrons. Since an electron has a minus charge, when an electron moves
along a wire, it is a negative charge. Current is understood to move in the opposite direction.
Current requires both a magnitude and a direction. By convention, current always moves in the
direction opposite to the motion of electrons. Look at the picture below, the blue arrow indicates
the direction of current while the red arrow indicates the electrons are actually moving in the
opposite direction.

The electrons in an atom can be either strongly or weakly connected to the nucleus. Electrons
that are weakly connected to the nucleus are called “free” electrons, and they are capable of
moving from atom to atom, meaning that they are not bound to one particular atom. You’ve
probably felt electrons move when you reach out to touch something and feel a little shock.

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A 'conducting' substance contains a large number of free electrons. In metal, which is a common
conductor, some of the electrons are strongly bound to the nucleus and some are free to move
between atoms. Electrons can pass through conductors easily.
In an ‘insulated’ substance there are only a few free electrons. These substances are not effective
at "passing" an electric current. It is relatively easier to run an electric current through conductive
substances than through insulated ones.

Circuits

In order for electricity to flow, electrons must be able to continuously travel. A helpful
troubleshooting tool is to start with the positive source, like the positive end of a battery, and use
your finger to trace where the electrons will go until you end at the negative or ground end of the
battery. When electrons flow, lights turn on, motors run, etc. For example, when you turn on a light
switch, it closes the circuit, electrons flow, and the light turns on.

Voltage

In order for a current to be generated between two points along a conductor, there must be
some factor that will cause the free electrons to move, or be pushed, in the desired direction.
This factor is called “voltage” and it is an electrical property between two points. An “electrical
differential” is needed between the extremities of the conductor in order to generate an electric
current. This differential is voltage. It is represented here by U or V. It is measured in volts
(abbreviated V).
Electrons, when separated from the protons, have energy. This energy is called voltage. When
electrons flow back to the protons, the flow is called current. When you have both voltage and
current, this is energy.

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A voltage source is in an electrical element that creates voltage in its terminals. It is customary to
mark the positive terminal (+) and the negative terminal (-). It is customary to sometimes mark
the voltage at the source terminals with the letter E.
Below are images of voltage sources:

The symbol of a voltage source in a circuit is:

A battery is an example of a voltage source.
What are battery voltages you are familiar with? _________________________________
A battery supplies constant voltage that cannot be altered while a power supply contains a
voltage than can be altered, making it useful for experiments.

When a current flows through an electrical component, we say it has a ‘voltage drop’.

Resistance

When electrons are in motion in a conductor, certain electrical elements resist the electric
current. The electrical property that restricts the current is called 'resistance’ and has the symbol
R. Resistance is measured in units of ohm which are marked by the Greek capital letter omega:
Ω. When electrons pass through a resistor, the resistor absorbs some of the energy. Absorbing
the energy means the voltage is reduced.
Different electrical components have different electrical resistances. Sometimes this resistance
is necessary while sometimes it is undesirable. For example, in a wire where we want current to
flow with as little resistance as possible, any resistance is undesirable. When the electric current

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needs to be restricted, for safety for example, we use a component called a ‘resistor’ to add
resistance. A resistor has a known resistance that does not change with time.
It is customary to use one of the following symbols to represent a resistor in an electric circuit:

The human body, like any other substance, has resistance. Resistance in the human body
depends, among other things, on the degree of moisture of the skin.

When the skin is wet, the body resistance is low and therefore a current can flow through it more
easily and becomes more dangerous. For this reason, it is especially important to be careful near
electrical appliances or electric sockets when wet.

Resistors and other elements generally have a resistance that is higher than 1Ω. And, here again,
prefixes are used to indicate high values of resistance. Therefore, for example, the electrical
resistance of dry human skin is normally in the 1MΩ-2MΩ range.

Comparatively, the electrical resistance of wet human skin is approximately 10 times less, which
significantly increases the possibility of electric shock.

Summary

Let’s summarize what we have learned about physical dimensions:

Electrical dimension Symbol Unit name Unit symbol
current I ampere A
voltage V volt V
R ohm Ω
resistance

Connecting Resistors in Series

When connecting resistors one to the other in a chain, this type of connection is called a
connection in series. The following diagram shows an example of three resistors connected in
series:

R1 R2 R3
A

The total resistance is the sum of the resistances of resistors connected in series:

Rt = R1 + R2 + R3 + ...

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Principles of Engineering

When connecting N identical resistors with R resistance, each in a series, the total resistance,
RTotal = N · R

The total resistance is also called equivalent resistance. The equivalent resistance of resistors in
a series is larger than that of each resistor. When resistors are connected in series in a circuit,
they can be replaced by a resistor with the same equivalent resistance, and the properties of the
circuit will not change.
For example, the following series of resistors:

A
can be replaced by an equivalent resistor:

Rt = R1 + R2 + R3 = 3 + 8+ 9 = 20 Ω

Ohm’s Law

Ohm’s law describes the correlation between the voltage, the current and the electrical
resistance of an electrical component.

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Principles of Engineering

When connecting a resistor to a voltage source, the voltage source creates a voltage drop on the
resistor, or in other words, causes an electric current to flow through it. A structure in which
resistance is connected to a voltage source is called an ‘electric circuit’.

The intensity of the current flowing through a component with resistance R within a regular

electric circuit is directly proportional to the voltage drop between its extremities, and inverse to

its resistance. In other words, the voltage (electrical energy) absorbed by the resistor is

proportional to the current. The voltage drop (voltage absorbed) is the current times the value

of resistance.


=

Where voltage is in units of V and resistance is in units of Ω, current is in units of A.

When the component’s resistance is constant, the higher its voltage, the higher the intensity of
the current that flows through it will be.

The following formulas derive from the previous one:

V=I·R =



Using Ohm’s law one must ensure that the three quantities (voltage, current, resistance) refer to
the same element. This element can be a particular resistor, but can also be the equivalent
resistance of several resistors.

Examples

Examples for calculating the electrical dimensions using Ohm’s law:
Using Ohm's Law, determine how much current in flowing through each circuit.

1. A 100 Ω buzzer is connected to a voltage source of 5V.
What is the intensity of the current flowing through the buzzer?

Solution:

R = 100 Ω, U = 5V

5
= = 100 = 0.05 = 50

Answer: The intensity of the current flowing through the buzzer is 50mA.

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2. An electric clock with 4.7 kΩ is connected to a voltage source of 220V. What is the
intensity of the current flowing through the clock?
Solution:
R = 4.7 k Ω = 4700 Ω, V=220V
220
= = 4700 = 0.047 = 47
Answer: The intensity of the current through the clock is 47mA.

3. A 5V voltage and 0.5A current are measured on a resistor. Calculate its resistance.
Solution:
V=5V, I=0.5A
5
= = 0.5 = 10Ω
Answer: its resistance is 10 Ω.

4. If you have a 4Ω resistor. What voltage is required at the resistor terminals to have a 5A
current flow through it?
Solution:
R = 4 Ω, I = 5 A
V = I · R = 5 · 4 = 20 V
Answer: A voltage of 20 V is needed.

Measuring Voltage and Current

We use a multi-meter to perform electrical measurements. To make a certain measurement, the
instrument should be set to the appropriate configuration, and the wires connected between the
right sockets and the points being measured.
The resistance of a component is measured when it is not connected in a circuit. On the other
hand, voltage and current are measured when the measuring device is connected to the
appropriate points in the circuit.
To measure the resistance of a resistor, the device should be set to the symbol Ω. One end of the
resistors should be connected to the COM port and the other to the Ω port.
To measure voltage, the device should be connected to the two points through which the current
flow is desired, without disconnecting anything in the circuit. The device should be set on the
symbol for “direct current” (V and above it a straight line).

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Let’s look at the following circuit:

This circuit has a resistor connected to V
the voltage source. To measure voltage
across the resistor, the point closest to
the positive side of the voltage source
(point B) should be connected to socket
labeled V on the multi-meter, and the
point closest to the negative side of the
voltage source (point A) should be
connected to the socket labeled COM on the meter.

To measure current, set the instrument on the mA (milliamp) symbol and insert the red multi-
meter wire into the socket labeled "A" on the meter. The
circuit should be "broken" at the point where we want to
measure the current, and the multi-meter inserted at the
disconnected point. The two ends of the "broken" circuit
should be connected to the two multi-meter wires, so
the current of the circuit must travel through the multi-
meter in order to complete the circuit.

To the right, is an image of a multi-meter specifying the
various symbols and entrances we will use to measure
resistance, voltage and current:

Below is a diagram illustrating two multi-meters
connected in one circuit. One is to measure voltage (V)
and the other is to measure current (A) in a circuit, in
which a single resistor is connected to a voltage source:

Voltmeter mA To measure voltage, the
COM Ammeter probes are placed at the
two points across which
R COM you are trying to measure
a voltage drop.
V
Voltage source To measure current the
circuit must be broken and
the two probes of the multi-
meter should be used to
complete the circuit. This
forces all the current of the
circuit to travel through the
multi-meter.

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Principles of Engineering

Worksheet: Electricity and Current

Fill in the blanks using the following words: Protons Neutrons Electrons

1. The center of an atom contains both ________________and ________________

2. If an atom contains 5 ________________and 4 ________________, its charge is positive.

3. Electrons are attracted to ________________

4. Current is the flow of ________________

5. When a battery is “fully charged”, all the ______________are separated from the protons

6. A conductor had a lot of free ________________ to move around.

Fill in the blanks using the following words: Positive Negative

7. Positive charged particles are attracted to ________________ charged particles

8. If you remove an electron from a stable atom, the atom now has a _____________ charge

9. Electrons physically leave out of the ____________ side of a power supply (e.g. a battery)

10. When referring to current, we say that it is coming out of the ________________ side of
a power supply

11. Calculate the missing values to complete the table below. Remember that units matter
(1000 Ω = 1kΩ ) and check out Appendix B on Unit Conversions.

R VI Formulas
100Ω 9V
12V 200mA = ∗
2.2kΩ
4.7kΩ 3mA
9V =


=

220V 15µA

60V 20µA

4MΩ 3µA

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Principles of Engineering

Soldering

Introduction

This unit will discuss the basics of soldering. The material will cover safety concerns, making a
good connection, the importance of keeping the tip clean, the use of flux, and some common
mistakes.

Safety

Before you turn on the iron, make sure you have a proper work environment. Place all the
necessary tools and materials within easy reach. The area must be clean and clear of debris.
Ensure you have at least two feet on either side of you and two feet in front that is clear of all
materials except parts to be soldered, the iron, solder, solder cleaner (gold foil or wet sponge).

Before turning the soldering iron on, please wear a pair of safety goggles, then make sure the
iron is in a holder designed to hold the iron. Hold the iron by the insulated handle, and always
watch the tip whenever you lift it from the holder. Never lay the soldering iron down.
To solder correctly, the tip of the soldering iron must be between 650° F to 700°F degrees. In
some special situations, higher temperatures may be used. This temperature will burn skin
instantly. In contact with flammable materials such as paper, or plastic, a fire may result. Always
treat the tip of the soldering iron with care and respect.

Background

Soldering is used to create an electrical and mechanical connection between two pieces of metal.
Usually, the metal is copper. Solder will “wet” to clean copper metal. Wetting is essential for
electrical conduction. Solder will not wet to any oxide covered metal. The solder will bead up like
a tiny drop of oil on water. It will neither create an electrical nor a mechanical connection.
Soldering is a three-stage process.

1. First, the metal is heated and cleaned. All oxides are removed.
2. Next, the melted solder wets to both pieces of metal, and fills the space between them.
3. Finally, the solder cools and solidifies creating an electrical and mechanical connection.

Soldering

1. Begin by putting a tiny amount of solder on the tip of the iron. This tiny amount of solder
is needed to create a thermal connection between the tip and the metals to be soldered.

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Principles of Engineering

2. Put the iron in contact with the pieces being soldered
3. Apply solder. Only touch solder to the metal parts, not the iron. The metal parts must be

hot enough to melt the solder and burn the flux or a joint will not form.
The biggest mistake people make when soldering is to apply solder to the soldering iron
tip itself, then touch the tip to the metal pieces.

Only touch solder to the metal parts, not to the iron.

The solder will melt and flow off the iron, but there is no flux on the metal parts.
Continuing to touch the solder to the iron tip will melt and apply more solder, but the flux
will burn off without cleaning the metal parts. If the parts are not cleaned, the connection
will not be reliable.

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Flux

Flux is necessary to clean the metal. The solder must be applied to the metal pieces to get the
flux onto the metal. Flux is an oil based acid that removes oxide when it burns. When you touch
the solder to hot metal, you will see a thin trail of smoke. This smoke is the burning flux.

Soldering Tips

It’s important to heat both items being soldered, and not just one of the base metals. A good
solder joint will look like a Hershey’s Kiss

Care for Your Iron

The tip of the soldering iron is made of iron. Iron oxidizes when exposed to air. The rate at which
the oxide forms is dependent on temperature. At high temperatures, the oxides form quickly.
These oxides are thermal insulators. A microscopic layer of oxide on the tip of the iron will drop
the temperature over 100 degrees. If the iron of the soldering tip gets exposed to air, it will
oxidize, and not be hot enough to heat the metal parts which won’t be able to melt solder. If your
soldering tip is black, do not use it.

Cover the Iron Tip with Solder When Not In Use

Oxidization is also known as rust. When iron rusts, tiny craters form in it. Flux cannot flow into
these craters, so it becomes almost impossible to clean, and your tip needs to be replaced. To
prevent oxidization, ALWAYS keep the tip covered with solder. Covering the tip with solder is
called tinning.

Never put the Iron back in the holder without first putting at
least one inch of solder on the tip.

Do not take the soldering iron out of the holder until you are ready to use. The first thing to do is
wipe off the excess solder from the tip. This process will always leave the iron tip clean and
protected with a thin layer of tin that doesn’t form an oxide.

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Toys In Motion Part 2: Electric Circuit

We’ve explored the mechanical system where form and power yields action. Different forms can
create different modes of movement. In this lab, we will focus on the power using electricity,
soldering together electrical components with an oscillating motor to create a vibrating toy, called
a “jitterbug”.

Materials and Tools

Component Actual Symbol Notes

DC Motor In future units we will go deeper into
motors. For now, this motor will spin
Switch when electricity flows. The motor is
rated as 3.7V

The switch will close or open the
circuit. Remember, you need a closed
circuit for electrons to flow.

Battery Note the voltage rating on the battery.
Does it meet the needs for spinning
the motor?

Battery Markings (+ and -) indicate the
Holder orientation of the battery and
connector pins.

Wire Conductive wire provides a pathway
for electricity to complete a circuit.

Protoboard Used for prototyping, the protoboard
Eraser has a grid of conductive holes to which
Paper Clip components and wires can be solder

Cut this to create “foot” or create an
unbalanced weight to attach to the
motor

Bend and attach to create structure
like legs

Pliers Pliers are an excellent tool to bend and
manipulate wire like a paper clip
Wire
Strippers Wire strippers have special holes
matching the gauge (diameter) of the
wire that can strip off the protective
plastic and expose the wire inside

50 Unit 4: Electricity and Ohm’s Law | CIJE