Lab for Mon 1 June

Tomorrow, you'll do a lab on Newton's second law (forces). There will also be a short quiz, based on the reading for tomorrow (Ch. 5).

DataStudio software

Abhishek wrote up a nice guide to the DataStudio software we use in the labs for acquiring and analyzing data. You can find it here.

Homework hints (problems due 28 May)

Since we're just getting started, I'll give you some hints as to how to go about tomorrow's problems. We went over problems 4 & 5 in class, so you should be OK with those I hope.

Problem 6: The main trick here is to keep track of the time in our equations very carefully. Object 1 starts moving T seconds earlier than object 2. If our clock starts at t=0 when object 2 starts moving, that means object 1 has been moving for T seconds already. Therefore, wherever we would normally write t in our equations for object 1, we should use (t+T) to account for the head start. With that in mind, since you're given the initial position and velocity for each you can just write down x(t) for each and find their difference.

Problem 7: Like the last problem, you know the starting position and velocity for each object, so write down the two x(t) equations. (a) The second ball is at rest when its velocity is zero. They'll collide when the two x(t) functions are equal. (b) Relative speed just means finding the velocity of each ball at the time of the collision and subtracting them.

Problem 8: You'll suspect it covers half the distance in half the time, but that's not quite right - the ball is steadily slowing down as it rises. Since it goes faster for the first half of the motion, it covers more distance. Write down x(t), and find out how long it takes to get to the top of the motion and what that maximum height is. Then evaluate x(t) at half that time and see how far it has gone.

The "lab" period

Just as a reminder, since I wasn't all that clear about it initially, the "lab" period is usually going to be more than just doing the lab procedure and analyzing the data. Sometimes we'll want to do problems at the board after the lab, or a second activity, and sometimes the TAs will just want to make an announcement. Even if that isn't the case, the TAs also want to use any remaining time to help you with upcoming homework.

The main point being: once you've finished the lab procedure, please ask the TAs if you are done, or if they need you to stick around. Even if they say you are done, you're free to stay and ask them for help with the homework if you like.

Lab for Thursday 28 May

Tomorrow, we'll be following a slightly different procedure than the other classes. You can find it here. The introduction (~6 pages) is an explanation of how trend lines work, so you have some understanding of what you're doing, but isn't strictly necessary to complete the lab. 

Notes on 1D motion

This covers yesterday and most of today. They don't cover anything that's not in the book for the most part, but you may find them useful.

Quiz 1 and its solution

You can find quiz 1 from this morning, as well as a solution, here.

First day's homework problems

By now most of you should be worrying a bit about whether you know how to do the first homework problems or not. Don't worry too much - we'll go over at least one of them in the lab period tomorrow, and you'll also have time during the lab period to ask questions.

For the first problem, you're given a function m(t) and want to maximize it. Find its maximum like you would any other function ... like you did in Cal 1 a million times.

For the second problem, constructing a unit vector is accomplished by dividing a given vector by its own magnitude, making a vector of unit length. So if you can find the separation vector and its magnitude, the unit vector is just dividing one by the other.

The third problem is to verify that in fact you did learn about vectors at some point. Magnitude should be easy. For the angle, use the dot (scalar) product. You'll remember how to do this.

Slides for 26 May (first class)

Here are the slides I'll be using during the first class. They contain all the official sort of information about how the course will work.

Homework for the first week

Homework is (probably) going to be a little different than what you are used to. We won't be doing online homework, for a variety of reasons I'll likely give in the first class. However, hand grading is not really a tenable option with the brutal summer schedule. The compromise is that I'm basically going to spot check your homework - I'll assign several problems, but grade only one. 

• For each class, except possibly days with exams, I will assign several problems (~5 typically). 
• At the start of the following class, I will ask you to turn in one, and only one, of these problems. You will not know in advance which problem I'll chose to grade. 
• The rest of the problems will not be graded, but you will get solutions for all problems.
• I will assign the problems about a week in advance, with about a week's worth of problems at once. This way you can work ahead if you want. 
• The homework for the first week is already posted. The first class is on Tuesday, and you have three problems assigned for Wednesday. At the start of Wednesday's class, I'll announce which problem I want you to turn in, and you'll turn it in.* 
• This will repeat pretty much every day, though you'll have the weekend to worry about Friday's problems.
• I'd like you to use the template format for homework. You don't need to print and write on the template, just use the same headings and follow the same format. You won't need the "Numeric Solution" box very often. 

This should all be clear after the first class. You are allowed to collaborate on homework, but everyone must turn in their own copy of the homework. By "collaborate" we mean "help" rather than "copy" - help each other out if you get stuck, check your answers, but don't just copy each other's work. 

*Ideally just that problem, but if you have other problems on the same sheet you can turn the whole page in. I'll only grade one problem, but we don't have to waste paper.

More detailed schedule

Here is a more detailed schedule than what is on the syllabus. I list for each class the main and secondary/tertiary topics, as well as lab procedures and exams (exams will be during the lab periods). I also list which chapters of the textbook (HRW) you should read before each class, and which sections (volume.chapter) of the Feynman lectures might be useful as supplemental reading.

Lab 1 (Wed 27 May 2015)

Your first lab experiment (Wed 27 May) will be on uncertainty analysis. The main idea is to learn how to handle data, particularly to assess its accuracy. You can find the procedure here.

As we'll discuss in class tomorrow, you will do 2-3 labs each week, but only have to write a formal report on one of them. The data from the other lab(s) you are not reporting on will be graded, but no writeup is required. Your weekly lab report is due the following Monday, and should follow the template provided.

Welcome to PH105-050, summer 1 2015

We'll be getting started in just a few days, here is some useful information about the course and some supplemental resources.

• Syllabus (UA only link, public link) - includes daily schedule
• Supplemental reading: the Feynman Lectures on Physics
• most of the relevant material is in volume 1
• I'll post a list of how the chapters correspond to the textbook
• related content from previous courses I've taught
• example HW, exams, notes, etc.
• ph105 - used the same textbook in Sum2012
• ph125 - same textbook for all instances
• ph101 - algebra-based, but many of the problems are similar
• lab procedures and schedule - sometimes we will use an alternate procedure for the listed labs. Check here to be sure.
• Math guide. It is by no means "short" as the title suggests, and I do not expect you to read the entire thing in detail. Rather, treat it as a collection of mathematical facts that you might find useful throughout the course.
• Problem solving template. I will go over this in lecture, but it is meant to give you a structure you can use to assist in solving problems. It will not make the process purely mechanical, but it should serve to guide your thought process in solving problems (particularly as they get more difficult later on). 
• Wolfram Alpha. If this thing can't solve your math problem, either it doesn't have a solution or you've posed the question poorly. Try this, or this, or this to see a few things it can do.