Welcome to Physics 7C

Emily West

ewest@physics.ucdavis.edu

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Agenda

Logistics: Syllabus & Web Page Clicker Setup Course Overview--the big ideas Simple Harmonic Oscillation Review Wave Introduction

What is Total Phase and why do we care?

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Some Logistics

Course Webpage: http://physics.ucdavis.edu/physics7

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Physics 7C Fall 2008, Sections A & B Syllabus

Welcome Back to Physics 7! This course is deliberately taught in a way to make it more consistent with what current research reveals about how students actually learn subjects like science. The lecture is not designed to function as the means by which you acquire the course content. Rather, it is to be used to provide focus and to provide a framework for your discussion/lab (DL) experience and the time you spend outside of class. Much of your learning will occur as you participate in various types of activities, experiments, and discussions in small groups and as a whole class in DL, and as you carry out the homework assignments between each DL meeting.

Lectures Lectures are on Tuesdays in Roessler 66. Lecture A is 7:30-8:50am. Lecture B is 9-10:20am. There will be seven quizzes, one during each lecture except the first on September 30 and the week of Thanksgiving break.

Instructors Emily West ewest@physics.ucdavis.edu Office hours: Monday 1 PM – 2 PM, TB114

Dr. Wendell Potter potter@physics.ucdavis.edu Office Hours: Thursday 3:40–4:30 158 Roessler

Email When using e-mail, please include “Physics7C” in the subject line. Be sure to include your return email address (and your name) in the body of your message, as it often does not show up in the email header. We would prefer replying to your official UC Davis email address.

Discussion/Labs There are eleven different DL sections for 7C, sections A & B. Each DL meeting lasts two hours and 20 minutes and meets twice each week in TB114 (across from Haring Hall). If you must miss a ,DL, you might be able to make it up, if there is another section still doing the same activities. You may attend another DL with the permission of the Instructor. Take a note signed by the Instructor back to your own DL Instructor at the following DL meeting. You may make-up no more than three DL meetings. NOTE: The lab fee for Physics 7C is $21.00 to cover the cost of materials. If you cannot pay this fee, you may be eligible for a fee waiver. Contact the Physics Office, 225 Phys/Geo, before the 20th day of instruction. Students who are Pell Grant Eligible automatically receive a fee waiver.

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Learning resources Course Tex t: “Physics 7C, Course Notes.” The text is available on the webpage as a PDF file. Web page (http://physics.ucdavis.edu/physics7): The Physics 7C web page has some additional course material. Updates and announcements will be posted there. Handouts: You will receive several handouts at each DL meeting. Lecture Presentations: Periodically, additional material will be posted on the webpage. Your Personal Learning Resource: You are responsible for organizing your notes, written materials from DL, text, lab workbook, etc., in a way that is effective for you.

Course expectations and grading: The responsibility for learning is yours! Your course grade in Physics 7C is based primarily on your performance on the quizzes and on the final exam. Extraordinary participation in DL or lack of participation can also affect your grade, as can in-lecture clicker questions. The lowest quiz score will be dropped in determining your quiz grade. You will also receive automatic credit for up to 15% of the clicker questions, which should be enough to account for any technological difficulties. Your grade is determined by whichever method benefits you more: 50% Avg of Quizzes + 45% Final exam + 5% Clicker score ± DL Grade 20% Avg of Quizzes + 75% Final exam + 5% Clicker score ± DL Grade

Exam s: The re will be seven quizzes and a final exa m. Ea ch quiz is given dur ing lectu re, and the final exa m occurs dur ing the UCD ass igned s lot—in th is case, We dne s day Dec em ber 10 th, 3:3 0-5:30pm. Test s a re closed book a nd closed notes, though key e quati ons from the mater ial will be ava ila ble on the exa ms. Calculat ors are allowed for tests unless advert ise d othe rwis e in a dva nce.

Grading: The test questi ons will be graded by assi gning a letter code that cha racterizes your res ponse. These codes wi ll be tra ns lated to a point va lue tha t will contribute to your fina l gra de. A de script ion of the mea ning of the cod e s will be post e d on the web s ite. If, after carefully com pa ring what you actually wrote on your test questi on a nd the descr iption of the code s , you believe the wr ong code was a ssi gne d, you may req uest a rec onsideration of the code as signed to a partic ular res pons e. To do this, attach to your te st the test re -grade form (availab le from the we bsit e ). Su bmit these to Emily West during the lectu re with in one we ek after the retu rn of the tests. (Wa rning: Do not alter your test in any way whe n su bmitting for a re grade. Alte red quizzes wi ll be turne d over to Student Judic ial Affairs – No exc e ptions .) Note : Tests sub mitted for reg rade are reg raded in their entirety, which ca n res ult in dec rea s ed sc ores.

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Quizzes: There will be seven quizzes, each given sometime during the lecture, each roughly 20 minutes long. There will be no make-up quizzes.

Final Exam: The final exam is on Wednesday, December 10th, 3:30pm-5:30pm. You must take the final exam at this time and day. If you cannot take the final at this time, do not take Physics 7C this session. The only exception is if taking the final at this time conflicts with observance of your religious practice – If this is the case, contact Emily West during the first week of class.

Clickers: During lecture, I will periodically ask multiple choice clicker questions to quickly gauge your understanding of the material. Clicker questions are worth 5% of your grade. Participation guarantees you full credit—please answer thoughtfully and with your honest beliefs so the class can best meet each student’s needs.

Discussion/Laboratory grading: The DL is central to the course. If you fail DL, you will fail Physics 7C. Your DL Instructor will determine your DL grade based on your preparation (consistency in completing the out-of-class assignments) and participation in the DL. Your TA w ill further discuss how this grade is determined. DL grades are:

HP: High pass – increases your course grade by 0.333 points (on the Registrar’s standard 4-point scale). However, a high pass will not raise an "A" to an "A+." Participation stands out as truly exceptional in DL. MP: Mid pass – increases your course grade by 0.167 points. Participation exceeds what is expected. P: Pass – does not change your course grade. Does everything that is expected of students in DL. A good solid record of participation. LP: Low pass – decreases your course grade by 0.333 points. Does not meet participation expectations. U: Unsatisfactory – decreases your course grade by 1.000 points (i.e., a whole letter grade: "B-" to "C-", or "B" to "C", etc.). Lack of participation is significant and affects the learning of other students. F: Fail the course (regardless of test and final scores). Level of participation in DL is totally unacceptable. Note: the majority of students receive a Pass grade in DL

Attendance in DL is mandatory. With two DL absences, your highest DL grade is a Low Pass. With three DL absences, your highest DL grade is Unsatisfactory. Four or more DL absences is totally unacceptable and you will fail Physics 7C. Low Passes and Unsatisfactory grades will also be given for chronic tardiness, leaving early, lack of active participation, incomplete homework, and behavior that contributes negatively to the productive functioning of the small groups.

Academic dishonesty: Cheating will not be tolerated. Cheating of any form is always immediately reported to Student Judicial Affairs for appropriate action. We appreciate any suggestions you may have to help us reduce the temptations and opportunities of academic dishonesty.

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Clicker Setup: Joining Class

1) Turn on your clicker; It scans for Classes

2) If it doesn’t scan automatically, hit enter (green button)

3) Find FAPHY7C1; hit enter

4) Display reads “ANS: FAPHY7C1;” hit enter

5) When you’ve successfully joined, display reads “ANS: wait for Q”

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PRS Clicker Setup: Student ID

1) Turn on your clicker

2) Press * to access Setup Menu

3) Scroll to find “ID;” hit Enter (green button)

4) Enter your Student ID so I can give you credit; hit enter

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Check Clicker Setup

In DL on Thursday, Friday, or Monday we talked about…

A) Three-phase diagrams and the heat pack

B) Waves and Oscillators

C) Steady-state flow in a fluid circuit

D) Slow down--I didn’t get my ID entered yet!

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Big Ideas of 7C

Wave Model Interference

Ray Model Optics

Field Model Electricity Magnetism

Quantum Mechanics

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Simple Harmonic Oscillation Review

How can we describe the motion of oscillating objects?

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Simple Harmonic Motion (SHM) Constructs

Amplitude: maximum distance from equilibrium Period (or frequency): amount of time required to

complete a cycle (or number of cycles per unit time) Equilibrium: position at which all forces acting on the

object sum to zero. Displacement: position of the object relative to

equilibrium Restoring Force: a force that acts on an object that

tends move it toward equilibrium Defining SHM: The restoring force is proportional to the

displacement. Anything missing? xF k x=−

uur r

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Mathematics of SHM

y=Displacement

A=Amplitude

T=Period

t

y

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Mathematics of SHM

y=Displacement

A=Amplitude

T=Period

t

y

In this image, which numbers, if any, show… Displacement?

1

4

3

5

2

6

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Mathematics of SHM

y=Displacement

A=Amplitude

T=Period

t

y

In this image, which numbers, if any, show…

1

4

3

5

2

6

Amplitude?

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Mathematics of SHM

y=Displacement

A=Amplitude

T=Period

t

y

In this image, which numbers, if any, show…

1

4

3

5

2

6

Period?

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Mathematics of SHM

y=Displacement

A=Amplitude

T=Period

t

y

y(t) = A sin (2 t/T)???

In this image, what is the mass doing at t=0 seconds?

A

T

T

A

Is the equation correct as is?

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Mathematics of SHM

y=Displacement

A=Amplitude

T=Period

t

y

y(t) = A sin (2 t/T + )

In this image, what is the mass doing at t=0 seconds?

In this image, what value does

have?

T

=phase

y(t) = A sin (2 t/T)?

A

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Making Waves

Watch waves How does the motion you are

watching differ from the motion of the mass-spring?

How is it the same? What new constructs are

needed to describe waves? What constructs can I control

when I start the wave? How do I change each one?

What moves from one end of the machine to the other?

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

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Wave Constructs

Waves: A transfer of energy without bringing along the mass. Particles in the medium get disturbed and collide,

but they stay oscillating about one position; they don’t travel with the wave.

The medium does not effectively move. The disturbance advances, that’s the wave.

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Graphing Wavesa) At a particular time (holding position constant)

b) At a particular position (holding time constant)

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Mathematics of Harmonic Waves

Displacement (y) is a function of both position along the medium and time. y(x,t)

In space, function repeats every wavelength In time, function repeats every period

t xy(x, t) A sin ( 2 2 )

T

λ= + +

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Longitudinal vs. Transverse Wave Polarization

Longitudinal Wave Transverse Wave

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