University of California San Diego, Department of Physics
Winter 2015 Physics 4A

PHYS 4A – Mechanics

Instructor: Sunil Sinha

Lecture: Tuesday and Thursday 2:00 PM - 3:20 PM

Location: York 2622

Discussion Section: Wed. 8:00 AM - 8:50 AM

Location: PCYNH 122

Weekly Quizzes: Friday 9:00AM - 9:50AM HSS 1330 Starting January 16th

PHY 4A Syllabus (PDF)

Professor Contact Information:

Sunil Sinha
Office Hours: Thursday 11:00AM - 12:00PM, or by appointment.

TA Information

TA: Animesh Gupta

TA Office Hours: Thu. 6:00PM - 7:00PM, Mayer Hall Addition 2623 (opposite to old 2702 Physics Tutorial Center)

General Course Information:

Text: Physics for Scientists and Engineers, Wolfson & Pasachoff, UCSD Edition, Addison-Wesley
Final: Thursday, March 19, 2015 - 3:00PM - 6:00PM

Grading: quizzes =60%, Final=40%.

If you are unable to view something or find any discrepancy, mail your queries to


Extra discussion/problem session will be at 4322 Mayer Room, Mayer Hall on Wednesday from 8am-9am.
Reminder: Professor Sinha will hold a special help session in Mayer Hall 4681 on Tuesday from 1 PM to 3 PM.

2) Professor Sinha will hold a special help session in Mayer Hall 4681 on Tuesday of Finals Week from 1 PM to 3 PM.
3) There will be a discussion/problem session during Finals Week at the usual place and time (i.e. Wednesday morning 8 AM to 8:50 AM in Pepper Canyon Hall 122). Change in venue or time will be posted if there is any.
4) The Final Exam will consist of 10 Multiple Choice problems + 2 problems which will be graded. Please bring blank sheets of paper or a blue book (in addition to red scantrons) to write your answers of these 2 problems.
All other rules for the regular Quizzes apply, including use of your 3-digit ID numbers, required use of red scantrons, allowed one cheat sheet (both sides), and no text books or devices with wireless connections allowed.

Homework 9 Solutions uploaded.
Reminder: Practice Final uploaded, and Important Announcements regarding Final.

Quiz 8 grades updated.
Quiz Analysis with class average updated.

Practice Final uploaded.
Quiz 8 grades uploaded.
Quiz Analysis with class average updated. Quiz 8 Solutions uploaded.

Homework 9 uploaded.

Important Announcements regarding Final and last two lectures.
Lecture 11 uploaded.

Quiz 7 grades uploaded.
Quiz Analysis with class average updated.
Quiz 7 Solutions uploaded.

Homework 8 Solutions uploaded.
The material covered for Quiz 8 (last quiz) is Chapter 14 only. There are some good examples for problems on equilibrium given in the textbook. If you read and understand them, plus practice on this week's Homework problems from Chapter 14, you will be prepared for Quiz 8.

Lecture 10 uploaded.

Homework 8 uploaded.

Quiz 6 grades uploaded.
Quiz Analysis with class average updated.
Quiz 6 Solutions uploaded.

Homework 7 Solutions uploaded.

1) The topics for Quiz 7 next Friday will include Chapter 12- Sections 2 through 5 (inclusive), as well as all of Chapter 13.

Lecture 9 uploaded.
1) Remember to fill out your CAPE evaluations.
2) There is a sign error in the 2nd last equation on the bottom of Slide 11, Lecture 9. It should read: fs= 2/5 M a(cm-x) = - Ma(cm-x) + Mgsin(beta).

Homework 7 uploaded.

Quiz 5 grades uploaded.
Quiz Analysis with class average updated.
Quiz 5 Solutions uploaded.
Office hour timing for today- 6pm to 8pm.

Homework 6 Solutions uploaded.
There will be a discussion session tomorrow (Thu) morning 8am at 5301 Mayer Hall (MH5301) to compensate for the short discussion session today. Sorry for the inconvenience caused today. The office hours for tomorrow is also extended by 1 hour and will now be from 6-8pm.

Lecture 8 uploaded.

Homework 6 uploaded.

Quiz 4 Solutions uploaded.
Quiz 4 grades uploaded.
Quiz Analysis with class average updated.
Homework 5 Solutions uploaded.

1) Internal inconsistencies in the formulation of the problem was noticed for Problem 1 (as per Version A) of Quiz 4 involving a block and a rough incline at an angle of 30 degree, which could have misled students. Thus this problem will not be graded.
2) Professor Sinha has decided he will not skip Chapter 10 after all, so lectures, homework problems and next week's Quiz will cover both Chapters 10 AND 11 (of course only including material covered in class).
4) Lecture 7 and Homework 5 uploaded.
3) Professor Sinha will be out of town next Tuesday. Lecture will be given by Professor Hirsch.

Correction in HW#4 solution of Q.26 (b). The answer should be 3J. Work done = change in potential energy= 1/2*200*(.04-.01).

Lecture 6 updated.
Quiz 3 grades uploaded.
Quiz Analysis with class average uploaded.
Homework 4 Solutions uploaded.

Quiz 3 Solutions uploaded.
For Question 4 of Version D, both B and D are considered as correct choices as the correct answer (0.49) was misprinted as 0.4.

Quiz 2 grades uploaded.
Lecture 6 uploaded. Homework 4 uploaded.

HW3 Solutions uploaded with Problem #81
For Quiz #3:
It will consist of Chapter 6.
Sorry for the change of instructions again, but you need to only write your PID and NOT bubble it. The Scantron detector does not work when both Exam Number(QuizID) and PID are bubbled. But you do need to bubble your QuizID.

Homework 3 Uploaded.

Office hours venue changed to Mayer Hall Addition 2623 (opposite to old 2702).
Quiz 2 solutions uploaded.

Quiz 1 grades with Scantron instructions uploaded in Grades section.

Homework 2 Solutions, Quiz 1 Solutions and Lecture 5 Uploaded.
Starting from Quiz 2, you may bring an 8 1/2x 11 inch regular sheet of paper (both sides) instead of the previous 5 x7 inch card.

Homework 2 and Lecture 4 Uploaded.

The Material covered for Quiz 1 includes Chapters 1,2,3 and Sections 4.1, 4.2, 4.3 and 4.4 of Chapter 4. It includes projectile motion.
Updated Lecture 3 with 2 more slides on projectile motion.

Homework 1 Solutions Uploaded.

Quiz ID generation now available here. Get your ID before Friday quiz!
Note: Quiz-IDs less than 100 require a leading zero (e.g. 017 for quizID 17)

Lecture 3 Uploaded.
Homework 1 Uploaded.

Course Syllabus updated.
No quiz tomorrow. Lecture tomorrow (Friday) 9 - 9:50 AM in HSS 1330

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