Challenges in implementing cross-disciplinary design experiments in a large scale introductory physics class; a case study

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Challenges in implementing cross-disciplinary design experiments in a large scale introductory physics class; A Case Study

By

Pushpaleela Prabakar B.E., Electrical Engineering National University of Singapore, 2013

Submitted to the Integrated Design and Management Program and the Department of Mechanical Engineering in Partial Fulfillment of the Requirements for the Degrees

of

Master of Science in Engineering and Management and Master of Science in Mechanical Engineering

at the

Massachusetts Institute of Technology June 2019

The author hereby grants to MIT permission to reproduce and to distribute publicly paper and electronic copies of this thesis document in whole or in part in any medium now known or hereafter created.

Signature of Author

...

Signature

redacted

Integrated Design and Management Program

Department of Mechanical Engineering May 24, 2019

Signature redacted

C ertified by ...

-David Robert Wallace Professor of Mechanical Engineering; MacVicar Faculty Fellow Thesis Supervisor

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Challenges in implementing cross-disciplinary design experiments in a large scale introductory physics class; A Case Study

By

Pushpaleela Prabakar

Submitted to the Integrated Design and Management Program and the Department of Mechanical Engineering on May 24, 2019 in Partial Fulfillment of the Requirements for the

Degrees of

Master of Science in Engineering and Management and Master of Science in Mechanical Engineering

Abstract

A set of new design-based physics experiments were jointly developed by the Electrical Engineering and Computer Science (EECS) and Physics departments and implemented in a large-scale, introductory physics course, 8.02 Electricity and Magnetism, at MIT. These were developed in response to student feedback indicating that overly structured experiments limit their grasp of the abstract concepts of electricity and magnetism. Consequently, each of the four in-class experiments has an open-ended, design component, exploring a practical application of the concepts. In addition, these experiments were built upon an "active learning" structure, whereby students interact with each other and with online materials during class. They were integrated into a class of >700 students, with 8 sections total (-90 per section), with pre- and post-experiment assignments to support and reinforce the material covered.

After each experiment, the students were surveyed to determine their self-assessment to gauge their understanding of the purpose of the experiment and assess whether sufficient time was allocated to the experiment. At the end of the term, the students were also surveyed to compare their experience with both the traditionally highly structured experiments and the design experiments conducted during the same semester. Results revealed that though the design experiments were more enjoyable for the students, they perceived the traditional experiments as more relevant to the lecture material.

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Acknowledgements

I

would like to thank Professor David Robert Wallace, my thesis advisor for inspiring me to write my thesis on a new pedagogical approach. I have always been amazed by the effort that he puts into making his classes fun and enjoyable.

I would like to sincerely thank Professor Jacob White for giving me this unique opportunity to develop the content and deploy the design experiments for such a large class like 8.02. 1 wouldn't have known we could use legos in MIT classes, if not for your creative ways of teaching. Your patience and guidance were instrumental in making this whole experience so enriching. I would like to also thank Peter Dourmoushkin for all the guidance that you gave me throughout the development process. I would like to thank Alex Shvonski, my partner-in-crime who made physics a lot more comprehensible than I would have imagined. Your constant encouragement and acknowledgment kept me going even though this was much harder than I expected it to be. Thank you Caleb Bonyun, Josh Wolfe and Gladys Velez Caicedo for your support and contributions in making these happen.

Writing a thesis in an area I knew nothing about was definitely a challenging task. It would not have been possible without Janice Melvold and Meredith Thompson who taught me so much pedagogy and also helped me shape my direction of the thesis.

My life path literally changed after going through the Integrated Design and Management program. Matthew S. Kressy, thank you for believing so strongly in me and bringing me to MIT. At MIT, I learned how to learn the right way and it would take this lesson with me throughout my life. Andy McInnis, you gave me the confidence that I can work well with my hands. Melissa Parrillo, you have been such great support. Thank you both!

To all my IDM friends, you all became my family from the day I walked in for the first day of orientation at IDM. I learned so much from each one of you personally and professionally. You encouraged me to put myself out of my comfort zone and do things that I thought I will never be able to do. The way I look at the world now is very different, thanks to all the amazing conversations I have had with you all. I wouldn't have chosen a better group than you to live through the MIT Firehose.

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List of Figures

Figure 1: Breadboard to Printed Circuit Board... 24

Figure 2: Plate Separation Experim ent ... 27

Figure 3: Plate O verlap Experim ent ... 27

Figure 4: Plate Overlap & Separation Experiment ... 28

Figure 5: A ccelerom eter ... 28

Figure 6: Concept Q uestion in M ITx... 29

Figure 7: Setup of Part 1 and Part 2 of Resistor Piano Experiment... 30

Figure 8: Setup of Generator Experiment... 31

Figure 9: Setup of Part 1 and Part 2 of Wireless Power Transfer Experiment ... 32

Figure 10: Survey results for "I understood the overall purpose of this experiment"... 36

Figure 11: Survey results for "I was able to complete all parts of this experiment without significantly rushing" ... 37

Figure 12: Word Cloud of responses for Capacitive Accelerometer Experiment ... 38

Figure 13: Word Cloud of responses for Resistor Piano Experiment... 38

Figure 14: Word Cloud of responses for Generator Experiment... 39

Figure 15: Word Cloud of responses for Wireless Power Transfer Experiment ... 39

Figure 16: Survey results for "I found Friday Problem Solving/Pset problems relevant to my understanding of the experim ent"... 41

Figure 17: Survey Results for "How much, if at all, did Part I of the experiment impact my success w ith Part II? Part I w as,"... 42

Figure 18: Survey Results for "The experiment helped me understand 8.02 material better." .... 48

Figure 19: Survey Results for "The experiment related well to other content in the course."... 49

Figure 20: Survey Results for "The experiment was enjoyable... 50

Figure 21: Survey Results for "What was your favorite experiment?" ... 51

List of Tables

Table 1: Number of Survey Respondents ... 35

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1 Introduction

1.1 Motivation

The premise of this thesis started with me questioning my proficiency as an engineer when I first started working in Qualcomm, an engineering company. As a graduate from a reputed university that provided a primarily theoretically based engineering education, I was both surprised and puzzled by the difficulty I encountered in applying theoretical knowledge to practical work. I was faced with the question: "what is the barrier standing between my knowledge and hands-on work?".

That question became my driving force at MIT. I came to graduate school to learn skills to primarily develop my hands-on side. The process of becoming hands-on was challenging and required enormous focus and dedication. I noticed that while I was becoming good at hands-on work, the theoretical knowledge was receding into the background. This is when I realized that like most people, when I am learning something new and difficult, I cannot be juggling multiple things at the same time. Hence once again, I saw myself compartmentalizing theoretical and hands-on work.

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To be ready for the demands of the twenty-first-century workforce, students need to be able to combine sound theoretical knowledge in science (physics, especially) and skills in practical problem-solving. It is even more important for students to have some experience in looking at problems from a cross-disciplinary perspective. This guided me to think about how students can effectively merge theoretical and hands-on learning, while they are doing their hands-on work.

Recognizing the need for a "curriculum oriented to the pressing challenges of the 21st century -societal, environmental, and technological", MIT started to rethink engineering education and started implementing initiatives (MIT, 2018). To achieve this, in the direction of merging the theoretical and practical application sides as well as promoting cross-collaboration between different departments.

To ensure greater integration of theoretical and hands-on learning for all the undergraduates and not only a self-selected few, MIT has recognized the importance of intervening in the early stages of an engineer's education, especially in the subjects under the General Institute Requirements. For an engineer, the introductory physics classes are the most important, yet they are often undervalued by students. Several reasons such as being required to take this class and not being able to relate to the material, added to this attitude towards this class. In most universities, the introductory physics classes are taught through direct instruction method. Even at MIT, it was traditionally taught through a lecture-based method until a decade ago when the Technology-Enabled Active Learning (TEAL) method was introduced.

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theoretical principles through hands-on work. Most of the materials were still very much based on formulas and problem solving on whiteboards. Though the students were shown some experiments, there was very little emphasis on doing experiments by themselves or creating something based on the material that they learnt. In other words, the experiments were primarily demonstrations and students were not investigating theoretical principles by themselves. "Maker component and mindset" was missing in the introductory physics class. Moreover, the students were not able to relate the material learned to the practical world.

While educators would agree that students learn best from active learning (HMELO-SILVER, DUNCAN, & CHINN, 2007), the crucial missing component for aspiring engineers was the integration of theory and practice. Recognizing that students were not adequately grasping the concepts, the faculty introduced a new set of design experiments that included instructional and open-ended design, that gave greater emphasis to the active quality of the learning experience. As detailed in the following sections, the experiments required students to draw on their theoretical knowledge and demonstrate their understanding through open-ended design. It was important to bring in the cross-disciplinary collaboration so that the experiments are based on interesting practical applications of these concepts. We now face the important task of determining the effectiveness of this approach in improving students' understanding, as well as identifying the

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this approach, I will analyze student feedback on these experiments, which were jointly developed by the Electrical Engineering and Computer Science (EECS) and Physics departments.

To avoid the experience that I and many other young engineers initially encountered n our careers, it is important for the students to learn effectively from the beginning to integrate theory and practice. Doing so requires thoughtful and complex teaching methods which would benefit the students in the long run. The TEAL approach recognizes this. Instead of being put off by the challenges, it is important to study them and find methods to overcome them. This is what would provide the students with the best education in the long run.

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2 Background

2.1 Lecture-based College Physics Class

Traditionally, physics classes in college are primarily taught as large lecture-based classes. The mode of instruction is such that the instructor lectures a large group of students in a big lecture hall. The knowledge transfer could be characterized as an "information dump" of physics concepts and formulas that assume that the students are able to grasp this information in this way. The lecture material typically follows closely a particular textbook.

According to the constructivist theory of learning, knowledge cannot simply be transmitted from teachers to learners: learners must be engaged in constructing their own knowledge. (Von Glasersfeld, 1987). Settings of this nature (transmission of knowledge from teacher to student) diminish the opportunity for students to develop the skill of free, spontaneous exchange of ideas and thus do not foster active learning. (Dori & Belcher, 2005) The usual mode of assessments for these kinds of classes are mandatory, highly structured laboratory experiments (possibly involving lab reports), quizzes and exams. Though the laboratory experiments are designed for students to rediscover the laws of nature, which supplements the limitations of "top-down" instruction to a certain extent, they certainly do not solve the problem (Dori & Belcher, 2005) The high failure

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classes based on the constructivist learning theory. As noted above this theory maintains that knowledge cannot simply be transmitted from teachers to learners: learners must be engaged in constructing their own knowledge. (Von Glasersfeld, 1987).Moreover, the department also understood that it is essential to promote social interaction during class time. The role of social interaction is central in teaching and learning science and in studying the world. (Dori & Belcher, 2005) Peers help each other by offering alternatives and sustaining reasoning activities, and individuals benefit from this interaction by integrating knowledge from peers and the environment. (Dori & Belcher, 2005).

2.2 Technology Enabled Active Learning (TEAL) class

In 2000, MIT developed the Technology Enabled Active Learning method of teaching the undergraduate physics class. The TEAL environment is a "carefully thought-out blend of mini-lectures, recitations, and hands-on laboratory experience, which are merged into a technologically and collaboratively rich experience for students". (Dori & Belcher, 2005) The students are assessed in various ways, through concept questions pre and post the visualizations and experiments, participation during hands-on experiments and weekly problem-solving sessions, problem sets, quizzes, and a final exam. The 800 students taking the class are subdivided into 8 sections of 100 students each. 10 students sit together at a round table in order to facilitate discussion among themselves. As we can see, TEAL uses an active learning environment which "encourages students to engage in solving problems, sharing ideas, giving feedback, and teaching each other". (Dori & Belcher, 2005)

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A typical day in a Teal class would consist of the lecturer going over the important physics concepts that the students need to understand and giving concept questions for the students to solve throughout the session to gauge their understanding. The students are asked to do the same concept questions a second time after discussing them with their peers. This facilitates discussion of the concepts among peers. Some days are dedicated to structured hands-on experiments so that students have a visual understanding of the concepts. In order to encourage students to reflect on their hands-on experiments, credit is given when students complete surveys conducted on the effectiveness of these experiments.

The Physics department initially adopted this method for the 8.02 course, the college level introductory physics class on Electricity and Magnetism, due to the learning difficulties faced by the students especially in the topic of electromagnetism. Unlike the concepts covered in 8.01, Classical Mechanics, which can be sensed visually, and sometimes also vocally and through touching, the concepts covered in 8.02 are in a realm of physics that is not readily accessible by any one of the five human senses. (Dori & Belcher, 2005) Students who are new to the topic of electromagnetism also found it hard to understand the subject using only mathematical equations, and the innate complexity of the underlying mathematics further obscures the physics. (Dori & Belcher, 2005)

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2.2.1 Hands-on Experiments in TEAL class

Learners "learn by doing" to accommodate new knowledge through experiencing and assimilating newly acquired knowledge into their current conceptual understanding. (Inhelder & Piaget, 1958) This is why the hands-on experiments are given so much importance in the TEAL class.

At the same time, students were still asked to do very simple hands-on activities that were highly guided, and feedback from the students indicated that the labs were "overly instructional" and did not help them understand the concepts.

A student going through a highly structured and content-focused lab is primarily focused on analyzing the data and checking whether it is feasible to finish the lab on time. Their brain is not fully engaged in the process and they may feel little reason or need to think more deeply about the physics content involved. (Holmes & Wieman, 2018) This is because all the decision making involved in experimental physics is done for the students beforehand by the instructors who designed the experiments when they think about the research questions and how to test them. Instructors are erroneously assuming the students will go through a comparable thought process as they follow the instructions in the lab manual to complete the experiment in the allotted time

(Holmes & Wieman, 2018)

Instead of obtaining a prescribed outcome, for example, measuring the value of acceleration due to gravity, providing students with experimental goals for which the outcome is either unknown or unexpected moves the focus away from what students measure and toward how they measure it. (Holmes & Wieman, 2018) This may reduce student frustration and the tendency to massage

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the data to get the expected results. It instead would inculcate more scientifically authentic and desirable behavior.

However, students cannot be given completely open-ended physics experiments which are typical in lab-based physics classes. While they might learn a lot from such an approach, it would be impractical to implement since TEAL is still a structured physics course and not a laboratory class. Class time allocation to such experiments and the availability of the instructors are limited in such college-level physics classes. The challenge is about finding an optimal balance between sufficient guidance and open-endedness in the design of the experiments to maximize a student's learning.

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2.3 Interdepartmental Collaboration for 8.01/8.02 TEAL classes

Given a large number of its undergraduates majoring in engineering fields, MIT is especially interested in teaching undergraduate physics as an applied physics class to prepare these future engineers to learn how to use these physics concepts while they are solving engineering problems. Given that solutions to engineering problems often lie at the level of fundamental physics, engineers need to have a good grasp of the physics concepts.

Initially, different departments at MIT were interested in teaching their own versions of the 8.01 & 8.02 classes. On one hand, this makes sense since engineering fields differ in their approaches to thinking about physics. They are not necessarily looking at things at a fundamental level, but are looking more one can apply these concepts to devices or applications. (Dourmashkin, 2019) To avoid a proliferation of numerous versions of freshman applied physics courses, physics department decided against an applied physics section and have successfully collaborated with various departments, including as Mechanical Engineering; Earth, Atmospheric and Planetary Sciences; and Math, to create the existing 8.01 and 8.02 classes.

The Physics and the Electrical Engineering and Computer Science (EECS) departments, in particular, started working together to develop a number of hands-on experiments that would go beyond a set of instructions, instead, requiring students to think about the physics concepts and how to apply them in a design setting. The design of these experiments has gone through multiple iterations before the first trial deployment of these experiments was done in Spring 2018. The trial was limited to one of the 8 sections in 8.02. Since the eight sections are usually coordinated, this

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introduced an enormous set of complications on testing and assessing homework problems. (Dourmashkin, 2019) The experience was mixed, at best.

Moreover, the initial trial focused more on the design part of the experiment than students' exploration of the physics concepts. It was observed that the students either jumped right into the design component of the experiment without thinking about the physics behind it or they were stuck in trying to understand the physics concepts and worked on the theoretical calculations without having sufficient time to do the design component of the experiment.

The goal in Spring 2019 was to implement the experiments in all the eight sections in 8.02. In order to ease the students into the design part of the experiment, it was essential to figure out how to carefully structure the experiment so that they were neither too instructional or nor too open-ended.

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2.4 Broader Learning Goals of the Hands-on Experiments

2.4.1 Physics department Goals

One of the primary goals of the Physics department in adopting the hands-on experiments is to visualize abstract concepts like capacitance and "breathe some life into the formulas" instead of students just memorizing them. Students need to actually be able to experimentally see how varying the different terms in the formula will cause a change, instead of just understanding what the symbolic terms represent.

Secondly, they need to take some form of data and to understand that data in the context of models. Physicists try to measure quantities in the world and build apparatuses that can measure them. In the process of collecting data, students are also learning how to use measuring devices, which is an essential skill required for physicists.

2.4.2 EECS department Goals

The perspective of the EECS department is to empower the students to build or design a practical application by understanding the physics concepts that they learn in the 8.02 class. The department did not want the students to leave the 8.02 class thinking that they only learned some vector calculus and feeling that they will never use what they learned in their life. They wanted the students to feel a greater ability to design something. Moreover, the department wanted the students to learn how to reason and make better decisions from their reasoning. Ultimately they envisioned students becoming comfortable designing something with their hands using the physics concepts learned. As a long term impact, the department is also interested in finding out whether students go on to take experimental classes or classes that involve electromagnetics.

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2.5 Broader assessment methods

Learning sequences are to be built around the design of the experiments in order to solidify the whole learning experience. Designing pre-experiment questions and post-experiment quantitative analysis, as well as testing some concept questions on midterms and final exams, are important to ensure that students take the experiments seriously. The students tend to think it is important if questions related to the experiment are on the problem set, and if they are not, they start to wonder why they are doing this experiment. If the concepts learned in the experiment are not tested, students are also likely to assume that they are not important (Dourmashkin, 2019).

The focus of assessment for these experiments should be on the process of the experiment rather than the product of the experiment. Assessments should be embedded within these design experiments so that students' learning can be monitored and supported in real time without interrupting the flow of learning (Murai et al., 2019). Incorporating the digital leaming environment such as MITx with these hands-on design experiments is one way to do this. The experiments need to be broken into different smaller tasks and the students need to answer questions and reflect on each task while they are doing the experiment.

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3 Methodology

3.1 Design-based Experimental exercises

A set of 4 design experiments were introduced in Spring 2019 for the 8.02 class based on the

feedback gathered during the trial runs in Spring and Fall 2018. The four design experiments are Accelerometer, Resistor Paper Piano, Generator and Wireless Power Transfer.

The unique part of these experiments is that they use simple and playful materials such as Lego Bricks, so as to make the experiment easy to visualize and fun for the students to learn the otherwise commonly considered dry concepts of electricity and magnetism.

3.2 Preparatory work for scaling up

3.2.1 Switching from breadboard to Printed Circuit Board

Figure 1: Breadboard to Printed Circuit Board

For the trial version of the experiments, the microcontroller circuit was built on the breadboard (Figure 1), especially since it makes it easier to change the components. Since the components were finalized, the design was changed to a Printed Circuit Board (PCB). This way, it is easier to

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accidentally. Moreover, the PCB gives a more presentable look to the students using the microprocessor, helping to lessen the psychological barrier to using them.

The initial version of the Printed Circuit Board was designed with the users in mind. The header pins that the users need to access to connect to various components of the experiments and equipment were placed on the edge of the PCB for easy access. The header pins were also labeled to make it easier to see how they might be connected. However, the final labels turned out to be much smaller than expected.

The Teensy 3.2 microcontroller and the driver components were placed on headers so that they could easily be replaced if they malfunctioned. A dip switch was added to switch the software code between the different experiments. All 70 boards required for the run in Spring 2019 were assembled at MIT using surface mounted and through-hole soldering.

The breadboards worked well for all the experiments and only minor modifications needed to be done, which will be discussed in the Challenges section.

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descriptive text were condensed and instead more pictures were introduced to illustrate the instructions.

The first objective was to pique students' interest and engage them in critical thinking through design-based experimental exercises. Thus, we "split the difference" by incorporating both instructional and design components. The structure was such that students applied their knowledge from the first, instructional part of each experiment, towards the second, design-focused part. The accelerometer experiment will be explained in detail in the following section to give a better picture of the structure of the experiments.

3.2.3 Preparation of equipment for the different experiments

Due to the large scale of the class, a lot of thought went into making sure that the equipment used for each of the experiments was easy to follow using the pictures in the instructions. Even minor details such as the colors of the various wires used in these experiments were considered, to avoid confusion for the students since they needed to closely follow the pictures to do their setup.

3.3 Accelerometer Experiment

The design objective of one experiment was to build a functioning accelerometer and optimize the signal output. In the instructional information on the experiment, students were asked to explore the properties of a parallel-plate capacitor formed by two metal plates.

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3.3.1 Instructional part of the accelerometer experiment

Students first investigated the dependence of capacitance on plate separation by stacking spacers in between the plates and measuring the resulting capacitance (Figure 2).

Figure 2: Plate Separation Experiment

Next, they varied the area overlap between the capacitor plates by shifting them laterally and measuring the resulting capacitance (Figure 3).

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They repeated the capacitance measurement again by increasing the separation between the plates and making a series of measurements with varying overlap area again (Figure 4).

Figure 4: Plate Overlap & Separation Experiment

3.3.2 Design part of the accelerometer experiment

After this instructional exploration of the concepts, students moved onto the design part of the experiment. Using lego plates, pieces, and 3D-printed springs, they built an accelerometer (Figure 5) and shake the lego plates to observe how the capacitance varies qualitatively. They were expected to make changes to the area overlap of the metal plates to detect the maximum change in signal amplitude to capture the change in capacitance.

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3.3.3 Developing Learning sequences for the design experiments

The design-based experimental exercises were made more relevant to students by having them

continue to think outside of class. For instance, the students use their experimental data to answer

problem set questions. Additionally, related prep set and Friday Problem Solving questions were

given in some cases to prepare them with the concepts to be explored in the experiments.

Moreover, during the experiment, while they were exploring the instructional part of the

experiment, they answered concept questions and open-ended questions (Figure 6) to guide their

thinking and understanding.

Dimnm: Olss the following with your partner. then wrte a brief Question: For a non-ideal, parallel-plate capacitor, does the ideal

response in the field provded. _{capacitance equation underestimate, overestimate, or equal the}

" How does the capadtance depend on plate separation? measured capacitance?

" For what range of separations did you obtain measurements?

" How does your data compare with the expected behavior of an Ideal

parallel-plate capactor? a) underestimate

b) overestimate

c) equal

Figure 6: Concept Question in MI Tx

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3.4 Brief Explanation of the other three experiments

3.4.1 Resistor Piano Experiment

In the first part of the experiment, students examined how the width, length, and thickness of the resistor paper affect resistance. After exploring the geometry of the resistor paper, they created a "keyboard" out of resistive paper, where the voltage measured across the paper at even intervals

would map directly to a musical scale (Figure 7).

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3.4.2 Generator Experiment

In the first part of the experiment, the students examined how the change in magnetic flux

generates a voltage in the oscilloscope and understand the phenomena from the waveform

perspective. They understood how the induced emf waveform on the oscilloscope changes with

different combinations of magnets of the same and opposite polarity and the combinations of

pickup coils affect (Figure 8).

For the design part of the experiment, they would have to use the lessons learned from the first

part to continuously light LED lights with a forward voltage of 2V and 3V with maximum

brightness.

pick-up coil - -a.

\.j LEDs in parallel .

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3.4.3 Wireless Power Transfer Experiment

In the first part of the experiment, the students examined how the resonance frequency of an LC circuit changes by varying the inductance of a coil. They had to first understand how the inductance changes by varying the number of turns in a coil with a fixed radius. Then they had to vary the

radius of the coil with a fixed number of turns to see how the inductance changes.

For the design part of the experiment, they had to use the lessons learned from the first part to design an inductor that could transmit power at a frequency of 60 kHz as far as possible (Figure

9).

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4 Results and Analysis

To understand the effectiveness of these experiments, only the affective responses of the students were measured and analyzed. Their conceptual understanding was not carefully assessed and analyzed. Though the initial intention when rolling out these experiments was to bookend the experiments with pre and post-experiment questions, this wasn't effectively carried out due to time constraints. The focus in this first implementation of these design experiments was on structuring and deploying them on a large scale, rather than assessing them. Still, students' affective responses alone produced interesting and surprising insights.

The Capacitive Accelerometer and Resistor Piano experiments were conducted before the Spring break and the Generator and Wireless Power Transfer Experiments were conducted towards the end of the semester. The Capacitive Accelerometer and Resistor Piano experiments were allotted the entire session, which was around 2 hours. The Generator and Wireless Power Transfer Experiments were given only 1 hour each, as the instructors had to cover other lecture material and concept questions.

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4.1 End-of Experiment Survey Design

The affective responses of the students were obtained anonymously after each design experiment through a Qualtrics survey.

4.1.1 Multiple Choice Questions in all the surveys were based on the 5-point Likert Scale:

1. 1 understood the overall purpose of this experiment.

2. I was able to complete all parts of this experiment without significantly rushing.

3. I found the Friday Problem Solving/Pset problems relevant to my understanding of the experiment.

4.1.2 Open-ended questions asked in all surveys:

4. What is one interesting thing that you learned from this experiment? 5. What could we have done to improve your learning experience? 6. What advice would you offer students doing this experiment?

To understand a bit about the demographics of the students, they were asked their year of study and also, if they were freshmen, whether they were taking the course as Pass No Record (PNR) or as graded. We wanted to determine whether taking the class as PNR or graded affected students' attitudes toward or perceptions of these novel experiments. The results showed no major differences, so this will not be discussed in the results.

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4.1.3 Extra Question asked in Generator and Wireless Power Transfer Experiments: 7. Which year of study are you in?

a. Are you taking this class as Pass No Record (PNR) or Graded?

8. How much, if at all, did Part I of the experiment impact your success with Part II? Part I

was,

4.2 End-of-Experiment Survey Results

The total number of respondents for each experiment can be found in Table 1:

Table 1: Number of Survey Respondents

Experiment Name Number of Respondents

Capacitive Accelerometer 542

Resistor Piano 502

Generator 428

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4.2.1 Students were asked if they understood the overall purpose of the experiment

I understood the overall purpose of this experiment.

a

Capacitive Accelerometer a Resistor Piano m Generator -Wireless Power Transfer 72.5S% 67J7%

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Figure 10: Survey results for "I understood the

Agree

overall purpose of this experiment"

The Resistor piano experiment had the highest percentage (72.5%) of students agreeing that they

understood the overall purpose of the experiment (Figure 10). The Generator experiment had the

highest percentage (21.48%) of students disagreeing that they understood the overall purpose of

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4.2.2 Students were asked if they were able to complete all parts of this experiment without

significantly rushing.

I

was able to complete all parts of this experiment without significantly rushing.

m Capacitive Accelerometer m Resistor Piano n Generator a Wireless Power Transfer

Disagree Neutral

Figure H1: Survey results

for

"I was able to complete all parts of this experiment without significantly rushing"

Interestingly, the Resistor piano experiment had the highest percentage (74.5%) of students agreeing that they were able to complete all parts of this experiment without significantly rushing, while the Generator experiment had the highest percentage (46.89%) of students disagreeing that they were able to complete all parts of this experiment without significantly rushing (Figure 11).

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4.2.3 For each experiment, students were asked to identify one interesting thing that they

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(40)

Figures 12 to 14 show the results of the most frequently appearing words in their open-ended

responses. One notable observation is that the number of highlighted words in Figures 14 and 15

is greater than that in Figures 12 and 13, indicating that the key concepts learnt in Generator and

Wireless Power Transfer Experiment are more varied than the key concepts learnt in the

(41)

4.2.4 Students were asked if they found the Friday Problem Solving/Pset problems relevant to

their understanding of the experimenL

I

found the Friday Problem Solving/Pset problems relevant to my understanding of the experiment.

n Capacitive Accelerometer 0 Resistor Piano w Generator v Wireless Power Transfer

42M 4L40%

3-V3"

34.27%

Dsaufee Neutral Agree

Figure 16: Survey results for "Ifound Friday Problem Solving/Pset problems relevant to my

understanding of the experiment"

Turning to students' perception of the relevance of problem sets to their understanding of the

material, the Capacitive Accelerometer experiment had the highest percentage (44.25%) of

students agreeing that they found the Friday Problem Solving/Pset problems relevant to their

(42)

4.2.5 Students were asked how much, if at all, art I of the experiment impacted their success

with Part II. Part I was,

How much, If at all, did Part I of the experiment impact my success with Part II? Part I was,

m

Generator m Wireless Power Transfer

extremely unhelpful somevhat unhelpul neutral smrw t helpul extremely helpful

Figure 17: Survey Results for "How much, if at all, did Part I of the experiment impact my success with Part II? Part I was,"

This question was only asked for the Generator and Wireless Power Transfer experiments; hence

these findings are based on less data than those presented earlier. For both the experiments, the

percentage of students who found them somewhat helpful is higher than those who found them

extremely helpful (Figure 17). The percentage of students who found them extremely unhelpful

and somewhat unhelpful are comparable and insignificant. This shows that students did find Part

(43)

4.3 End-of Experiment Survey Analysis and Discussion

These first three survey questions indicate how the students felt about the experiment on the day of the experiment. It can be observed that there is a correlation between their being able to finish the experiments without rushing and their being able to understand the overall purpose of the experiment. The results of the survey results would be discussed along with the observations by the instructors made during these experiments.

4.3.1 Capacitive accelerometer experiment

Students were intrigued by the first experiment's use of Legos. It was eye-opening for them. Lego was one of the most frequently mentioned words in the word cloud of common answers (Figure 12) for the question "what is one interesting thing that they learned from this experiment" . Moreover, words from the capacitance equation, such as the plate area, also show evidence of them understanding concepts better.

In the same word cloud (Figure 12), it's notable that students mentioned edge effects as one of the interesting things they learned in the capacitive accelerometer experiment. This result is supported by to an instructor's observation that students consulted her more about edge effects on a parallel plate capacitor after doing this experiment, which was not common in previous years. Students

(44)

4.3.2 Resistor piano experiment:

The Resistor Piano experiment scored the highest percentage (72.5%) of students agreeing that they understood the overall purpose of the experiment (Figure 10). However, the associated word cloud (Figure 13) indicates that they may have missed the whole point of the experiment. From their saying they understood the concepts we cannot necessarily infer that they did. When probed further on the experiment, they didn't understand it was about voltage divider concepts and to be explained. This discrepancy might be attributed to the Dunning-Kruger effect where the students may not even know how much they understand because of the lack of expertise and knowledge about voltage dividers.

Moreover, it was observed that the students may not have met both physics goals of using the measuring equipment and understanding the formula. Having to learn both about the resistance formula and the voltage divider concept on the same experiment, may have overwhelmed them and thus prevented them from getting both concepts out of the experiment. Their worksheet drawings also indicated that the majority did not fully grasp both concepts. While students felt that they completed the experiment without having to rush, when they were closely observed, it was widely agreed by the instructors that they hadn't adequately explored the design part. Given students' perception that they had grasped the concepts despite, the instructor's skepticism, it could be termed as a "false positive".

(45)

4.3.3 Generator experiment

Results of the Generator experiment took a hit perhaps due primarily to insufficient time allocated for the experiment. The entire experiment was designed to carried out within 2 hours. However, at the last minute, the experiments ended up being allotted only one hour to allow for more coverage of material in the lectures.

This especially undermined the design part of the experiment because that is the part of the experiment which was expected to provide students with a deeper understanding of the concepts. Since it occurs towards the end,some students were not even able to get to it. This experience underscores the importance of allocating the two full hours for these design experiments.

Moreover, it's possible that some of the problems in planning and structuring these experiments could be attributed to "expert blindness". Firstly, the instructors already had, of course, a deeper understanding of the concepts compared to the students. Each experiment took multiple weeks for the instructors themselves to design and hence they also understood the aims and the purpose of the experiment better than the students. In an effort to direct the students to explore what the

instructors explored during the design of the experiments, they may have miscalculated how much time someone who doesn't know that material at all would need to do the parts and understand the

(46)

4.3.4 Wireless power transfer experiment

In case of the wireless power transfer experiment, it was communicated earlier that it would be allocated only one hour and both the structured and design parts were carefully designed such a way that students would have sufficient time. It was also designed based on the observations and feedback received through the generator experiment.

4.3.5 All experiments

There is an interesting correlation between the results of the word cloud and the students' perception of their understanding of the overall purpose. More words were highlighted in the last two experiments, generator, and wireless power transfer, (Figure 14 and Figure 15) which appears to have a lot more variety in what the students reported that they learned. This correlates to the lower percentages these experiments received in the survey question of their understanding of the overall purpose (Figure 10). Whereas the number of words highlighted in the first two experiments, capacitive accelerometer and resistor piano, (Figure 12 and Figure 13) is much lesser and these experiments have a higher percentage of students reporting that they understood the overall purpose of the experiment (Figure 10).

(47)

4.4 End of Semester Survey Design

Towards the end of the semester, students were asked regarding some questions regarding the six experiments done during the semester, both the newly introduced design experiments and non-design, traditionally highly structured experiments. 300 students responded to this survey.

To understand a bit about the demographics of the students, the year of study and also, if they were freshmen, they were asked if they were taking it as Pass No Record (PNR) or as graded. Moreover, they were also asked about their intended major. The results for the demographics questions would not be discussed in detail as they show

4.4.1 Multiple Choice Questions askedfor each experiment based on the 5-point Likert Scale:

The experiment helped me understand 8.02 material better. The experiment related well to other content in the course. The experiment was enjoyable.

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4.5 End of Semester Survey Results

4.5.1 Students were asked if the experiment helped them to understand the & 02 material better.

I

The experiment helped me understand 8.02 material better.

m Capacitive Accelerometer u Faraday Cage a Resistor Piano a Dipole In a Helmholtz Col s Generator . Wireless Power

MOWgr- Neutal Are

Figure 18: Survey Results for "The experiment helped me understand 8.02 material better."

Dipole in a Helmholtz coil scored the highest percentage of students agreeing

(58.5%)

that

experiment helped them to understand the 8.02 material better (Figure 18). Wireless Power

Transfer scored the lowest percentage of students agreeing (44.74%) that experiment helped them

to understand the 8.02 material better (Figure 18).

(49)

4.5.2 Students were asked if the experiment related well to other content in the course.

The experiment related well to other content in the course.

m Capacitive Accelerometer m Faraday Cage s Resistor Piano a Dipole In a Helmholtz Coll w Generator . Wireless Power

Figure 19: Survey Resultsjf

Il II

31.2aw

Si','

Agree

or "The experiment related well to other content in the course.

Dipole in a Helmholtz coil scored the highest percentage of students agreeing (60.34%) that

experiment related well to other content in the course. Wireless Power Transfer scored the lowest

percentage of students agreeing (49.49%) that experiment related well to other content in the

(50)

4.5.3 Students were asked how much they found each of the experiment enjoyable.

The experiment was enjoyable.

m Capacitive Accelerometer a Faraday Cage m Resistor Piano e Dipole In a Helmholtz Coll . Generator * Wireless Power

m

ii

I

DIsaee Neutral Ag

Figure 20: Survey Results for "The experiment was enjoyable."

Resistor piano scored the highest percentage of students agreeing (58.5%) that the experiment was

enjoyable. Faraday's Cage, which is a traditional experiment, scored the lowest percentage of

students agreeing (40.47%) that the experiment was enjoyable (Figure 20).

2X*M

(51)

-4.5.4 Students were asked what was their favourite experiment.

What was your favourite experiment?

* Capacitive Accelerometer

* Resistor Piano

* Generator

*

Faraday Cage

* Dipole in a Helmholtz Coil

* Wireless Power Transfer

Figure 21: Survey Resultsfor "What was your favorite experiment?"

Resistor piano experiment unanimously won the favorite experiment (39%) title by a large margin (Figure 21). The following two favorite experiments are Wireless Power Transfer and Generator Experiments. These top 3 favorite choices among the 6 experiments surveyed were the design experiments.

(52)

4.6 End-of Semester Survey Analysis and Discussion

The resistor piano experiment scored the highest percentage (39%) on the question on students'

favorite experiment (Figure 21), which is in line with the previous survey results obtained when

they were asked to rate their understanding of the purpose of the experiment and whether they had

sufficient time to complete the experiment. However, at the end of the semester survey results, the

resistor piano scored one of the lowest percentages for the question "The experiment helped me

understand 8.02 material better" (Figure 19) and "the experiment related well to other content in

the course" (Figure 20). This is in-line with the survey question on whether the Friday Problem

Solving/Pset problems were relevant to their understanding of the experiment (Figure 16).

Moreover, when students were asked what their favorite experiment was (Figure 21), the top 3

favorite choices, (resistor piano, wireless power transfer, and generator) among the 6 experiments

surveyed were the design experiments. This is in line with the results obtained in the survey

question (Figure 20), "experiment was enjoyable", where resistor piano, generator, and wireless

power transfer experiments were the top three percentages of students agreeing that the

"experiment was enjoyable". This shows that students made the decision on their favorite

experiments primarily based on how enjoyable they felt the experiments were.

(53)

4.6.1 Design Experiments Vs Non-Design Experiments

The design experiments rated more on the enjoyable side compared to the non-design experiments which were rated more relatable to the material taught in the class and helped them understand the material better. The lack of understanding and relatability of the lecture material in the design experiments may be due to various reasons during the implementation of the design experiments.

Firstly, since the design experiments were running for the first time in such a large scale level, the hardware that was developed specifically for these experiments started to malfunction over time. Since the hardware is like black boxes to the students, when their setup is not working, it takes time for the students to realize that it is not because of their setup but because of the hardware. Sometimes, what they ended up getting out of the experiment was trying to get the hardware to work instead of doing the experiment to learn the physics concepts. In the case of the non-design experiments, the equipment used to conduct the experiments were off--the--shelf experiments sets sold by education companies such as Pasco, which are well tested and their quality was ensured.

Secondly, the design experiments were initially designed to be done for two hours with a lot more parts in the instructional part of the experiment. However, when they were run, some of the design experiments were only allocated one hour or even less than that by the instructors. Some instructors

(54)

In the case of the non--design experiments, due to the absence of the design part, the time allocated for these highly instructional experiments were sufficient. The concept questions asked in these experiments were relatively straight forward multiple choice questions and not reflective in nature. Since they have been done earlier, the instructors knew exactly how much time to allocate these experiments as well. This may have led to the perception that the students understand the material of the non-design experiments more than the design experiments.

Thirdly, since the experiments were being done for the first time, the learning assistants (who are undergraduate students who have taken this class before and done well in the class) were not fully aware of how to guide the students conceptually since they have not done them before. The students had to heavily rely on the instructors who designed these design experiments when they had questions regarding the concepts. Moreover, also due to hardware malfunction, the instructors had to focus on fixing the hardware issues instead of focusing on clarifying the students' doubts and misconceptions.

In the case of the non--design experiments, since the learning assistants have been done these experiments before, they were able to help the students better instead of just relying on the instructors to help them out. Moreover, they were able to focus on the students helping students to clear their conceptual misconceptions rather than fixing the hardware since the equipment used in these non--design experiments were well tested previously.

(55)

Firstly, the design experiments used simple and playful materials like legos and paper, which made it much more fun and easy to use. They were fascinated with the fact that they could use such simple materials to do these experiments and these experiments allowed them to explore their "maker" side. The visual (LEDs) and auditory feedback (audio generated in headphones) that the students obtained during these experiments also allowed them to enjoy it more since they were intrigued by them. This was primarily missing in the non--design experiments.

Lastly, due to the open--ended nature of the design part of the design experiments, every student may have a different solution to the design problem. This allowed the instructors to instill a competitive nature into these experiments, which made it enjoyable for the students. For example, the design part of the wireless power transfer was turned into a competition among students from different sections, where they were asked to break the 8.02 record coil separation distance. The competitiveness brought out the motivation in the students to make their coils better, making it more fun and engaging. Since the non-design experiments were pretty much the same for all the students, there would not be an avenue to make it competitive for the students.