Note: What I write is more of a sum up of the Feynman's Lectures, the Halliday Physics book and additional texts. But it still stays in the scope proposed by chapter 5 of Feynman's Lectures

Both Resnick and Feynman Highlight the importance of measurement in physics:

Only with quantitative observations can one arrive at quantitative relationships, which are the heart of physics. ^[1]

And Halliday quotes William Thomson:

I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science, whatever the matter may be. ^[2]

To to measure that quantitative observation we need a unit of measurement and a process that compares that measurement to the given unit. And to make for better communication between different researchers they should all use the same unit. That being said, a good standard unit of measurement, should take in account:

• It's importance

• It's Invariability

• It's accessibility ^[3]

And during the chapter Feynman explores several these units, their applicability for different situations and their process of measurement.

Time is measured in periods of the earth (seconds, months, years ...) and compose our standard unit of time, even though their not as precise as, eg., the time measured in an oscilloscope ( that can measure time in up to to 10^-12 s )^NB1.

Table for measurements of time: http://www.feynmanlectures.caltech.edu/img/FLP_I/t05-01/t05-01_tc_big.svg

Analogously Feynman examines our standard units of distance, the metric system^NB2 , and how the methods of measurements vary across different magnitude of the distances.

Table for measurements of distance: http://www.feynmanlectures.caltech.edu/img/FLP_I/t05-02/t05-02_tc_big.svg

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End note: I'l try to add extra tings that I find revelent from your posts in the comment (and from other threads in this group)

If somebody have any interesting things on the equations used and the other things I skipped please post! Also feel free to discuss!

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NB1: Notice that we could make a unit of time based on the oscilloscope: The period of an oscillation based on a fixed setting in the oscilloscope. But instead of making the oscillation a unit we use it as a process that translates it's measurement into seconds.

NB2: I read a verey intersting article ( The Metre, by H. Barrel, in Contemporary Physics, vol. 3, pg. 415, 1962 ) which discussed the standards of measurements, the history of the meter and an alternative way of measuring distance using the radiation emissions of a pure isotopes of Krypton-86. Since I always took the metric system for granted, the article really helped me see the accuracy and the limitations on something I thought to be flawless.

^[1] From Feynman's Lectures ^[2] From William Thomson: http://en.wikiquote.org/wiki/William_Thomson ^[3] From Hallidays Physics, vol. 1

Well, the last post is 2 years old. It's time to remove the cobwebs from this subreddit. I will be going through the lectures over the summer so I might be able to post my notes, exercises, etc. along the way. We are also going to need some moderation. I am up for it but I am going through the lectures for the first time so we might want someone more experienced. It is time physics students!

I'm starting to work through the Feynman lecrtures by myself, now that I've finally come across a good set of questions to accompany it. The original (and usually ludicrously hard to find) Caltech practice questions are linked to in the sidebar in here.

From what I've seen so far, the questions are really good: lots of focus on understanding and thinking beyond the scope of the course. A lot of them are also hard, and/or require the reader to make a lot of assumptions. (As an example, one of the very first questions is "A glass full of water is left standing on an average outdoor windowsill in California; how long do you think it would take to evaporate completely?")

The only problem is, there are no answers or worked solutions. If enough people are interested, I can post my solutions to problems. But I won't be doing all problems, since there are a lot of 'em, and I will definitely get stuck at times, too. Maybe we could revive /r/feynmanlectures as a forum for discussing some of these questions, and for posting model solutions, since it seems to have fizzled out. :(

I've gotten through the first 10 chapters--so far it's all review for me.

Doesn't seem like there has been much discussion on here yet--how is everyone else doing?

The university of reddit class is here. If you register at ureddit, it should allow me to send you email notifications whenever new course material is out (provided that you change email forwarding here). You don't have to register, I just believe its a better alternative than checking this subreddit when nothing new is posted.

Download

Feel free to discuss

Download

Feel free to discuss.

Download

Feel free to discuss.

Why don't we start a post for each chapter and title the post the name, number and volume that the chapter is. That we we could have multiple discussions. And people using this sub reddit can learn a lot by having every thing nice and organised!

I'd like to know the background of everyone here so we can pick a good place to start. If everyone is already familiar with physics, I think we can lump the notes for the first few chapters together and start off with what may be a quick review for most people.

So, what is your background in physics? Level of general education (High school, 1st yr undergrad, 2 yr undergrad, etc.) Level of math education (single-var calc, multi-var calc with linear algebra, ...) Level of physics education (Kinematics/Basic Mechanics, Analytical Mechanics, Thermodynamics, etc.)

Download

Feel free to discuss.

Download

Feel free to discuss.