PHYS 20: General Physics
FALL 2012
COURSE NEWS
- 11/29/12: Note on Homework 7: 4.1, 4.4, 4.6, and 4.16 were each worth 2 points; 4.2, 4.5 and 4.7 were each worth 3 points; 4.3 and 4.8 were each worth 4 points.
- 11/19/12: Note on Homework 5: All problems were worth 2 points, except 3.7, 3.14 and 3.15 were each worth 3 points.
- 11/17/12: It has come to our attention that in some editions of K&K problem 3.20 contains a major typo. The retarding force should be F=-bmv, NOT F=-bv. If this error isn't fixed, the problem is unsolvable.
You can confirm the error yourself by checking the units on the hint. If F=-bv, then b has units of force/velocity which is mass/time. The terminal velocity given in the hint is (gamma*u - g)/b, which has units of acceleration/(mass/time), or velocity/mass instead of velocity like it should be.
It should be noted that F=-bmv is a very strange retarding force, and doesn't look like normal air resistance (due to viscosity or turbulence). This is a poorly written problem!
- 11/7/12: The PSR is closed on Monday, 11/12, for veteran's day. The TAs will be available on Tuesday 11/13 from 2-3 PM in Broida 3302. Please note the room change.
- 11/7/12: Notes on the Midterm, Problems 1 and 2:
- 1 b) If you had 4 out of 5 forces correct (words and equations) you got full credit. Please make sure you understand them all correctly.
- 1 c) Many people said that everything in the universe has mass. There are plenty of massless particles. For example, you interact with photons (particles of light) everyday. You don't really need to know more about this for phys 20, but you should be aware of it.
- 2) The problem asked for the first time interval, but some people calculated the full time interval. If you clearly did this correctly, and calculated t1 correctly in an intermediate step, then I gave you full credit. Many people did not do this correctly, so please try to understand the solution.
- 11/2/12: Several of you have asked whether blue books are required for the midterm. They are not necessary; paper will be provided.
- 11/1/12: We've posted the Chapter 3 discussion problems from the 11/1 recitations.
- 10/30/12: Dirk has decided to cancel problem set #5 due to the midterm. It will be replaced with a different problem set #5, due the following Monday.
- 10/29/12: Some notes about the homework: Each homework set is graded out of 25 points. For Homework 1 each problem was worth 2 points, except the last problem which was worth 3 points. For Homework 3 each problem was worth 2 points, except 2.10 which was worth 1 point. For problem 2.12, the problem technically asked for half the time interval, so it should be half the time given in the solutions. Both answers were given full credit.
- 10/26/12: Since not all recitations made it to the capstan question from Problem Set 4, we have posted notes for the problem.
- 10/18/12: We have had many questions about whether the lecture on Wednesday 11/21 before Thanksgiving will be held. The lecture will be held as normal, but for the convenience of students who need to travel, the same lecture will also be delivered on Monday 11/19, 6:15-7:30pm immediately following the normal lecture in Broida
1640 1610 (sorry for the error!).
- 10/3/12: It has come to our attention that some students do not yet have the textbook because the bookstore has run out. We have posted a scan of the homework problems for this week.
- 9/21/12: The recitations on Thursday, 9/27, will not be held, as there will not yet have been any lectures.
Instructor: Dirk Bouwmeester
E-mail: bouwmeester@physics.ucsb.edu
Office Hours: R 2pm-5pm in Broida 4123
TA: Brian Pepper
E-mail: bpepper@physics.ucsb.edu
Office Hours: M 12pm-3pm in Broida 1019 (PSR)
TA: Amy Thompson
E-mail: amy@physics.ucsb.edu
Office Hours: M 10am-1pm in Broida 1019 (PSR)
Lecture: MW 5-6:15pm, Broida 1610, Dirk Bouwmeester
Recitation #1: R 12-12:50pm, Phelps 3505, Amy Thompson
Recitation #2: R 1-1:50pm, South Hall 1430, Amy Thompson
Recitation #3: R 2-2:50pm, Girvetz 1115, Brian Pepper
Recitation #4: R 3-3:50pm, Girvetz 1115, Brian Pepper
Problem sets: Due Mondays at 5pm (before lecture), in box outside Broida 1019 (PSR), 30% of grade
Midterm: Monday, Nov. 5th, 5pm-6:15pm in Broida 1610, 30% of grade
Final: Tuesday, Dec. 11th, 7:30pm-10:30pm in Broida 1610, 40% of grade
Required Textbook: An Introduction to Mechanics by Daniel Kleppner and Robert Kolenkow (K&K)
Material: We will cover the first five chapters of K&K
PROBLEM SETS
Due to the course's unusually large enrollment, we ask that you prepare your problem sets as follows: include all of your work, but also staple a cover sheet to the front including all of your final answers on one page. Problem sets will be posted below and are due at 5 PM on the due date (usually Monday).
LATE PROBLEM SETS WILL NOT BE ACCEPTED WITHOUT PRIOR APPROVAL.